delta-islands.c: remove the_repository references
[gitweb.git] / builtin / pack-objects.c
index e9d3cfb9e33a6b874751ac6acc5aac2361d4a58d..7812c2b1f32ef688b365de3b33e564a8bf502b49 100644 (file)
@@ -1,5 +1,6 @@
 #include "builtin.h"
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "attr.h"
 #include "object.h"
 #include "streaming.h"
 #include "thread-utils.h"
 #include "pack-bitmap.h"
+#include "delta-islands.h"
 #include "reachable.h"
 #include "sha1-array.h"
 #include "argv-array.h"
 #include "list.h"
 #include "packfile.h"
+#include "object-store.h"
+#include "dir.h"
+#include "midx.h"
+
+#define IN_PACK(obj) oe_in_pack(&to_pack, obj)
+#define SIZE(obj) oe_size(&to_pack, obj)
+#define SET_SIZE(obj,size) oe_set_size(&to_pack, obj, size)
+#define DELTA_SIZE(obj) oe_delta_size(&to_pack, obj)
+#define DELTA(obj) oe_delta(&to_pack, obj)
+#define DELTA_CHILD(obj) oe_delta_child(&to_pack, obj)
+#define DELTA_SIBLING(obj) oe_delta_sibling(&to_pack, obj)
+#define SET_DELTA(obj, val) oe_set_delta(&to_pack, obj, val)
+#define SET_DELTA_EXT(obj, oid) oe_set_delta_ext(&to_pack, obj, oid)
+#define SET_DELTA_SIZE(obj, val) oe_set_delta_size(&to_pack, obj, val)
+#define SET_DELTA_CHILD(obj, val) oe_set_delta_child(&to_pack, obj, val)
+#define SET_DELTA_SIBLING(obj, val) oe_set_delta_sibling(&to_pack, obj, val)
 
 static const char *pack_usage[] = {
        N_("git pack-objects --stdout [<options>...] [< <ref-list> | < <object-list>]"),
@@ -43,7 +61,9 @@ static const char *pack_usage[] = {
 static struct packing_data to_pack;
 
 static struct pack_idx_entry **written_list;
-static uint32_t nr_result, nr_written;
+static uint32_t nr_result, nr_written, nr_seen;
+static struct bitmap_index *bitmap_git;
+static uint32_t write_layer;
 
 static int non_empty;
 static int reuse_delta = 1, reuse_object = 1;
@@ -53,7 +73,8 @@ static int pack_loose_unreachable;
 static int local;
 static int have_non_local_packs;
 static int incremental;
-static int ignore_packed_keep;
+static int ignore_packed_keep_on_disk;
+static int ignore_packed_keep_in_core;
 static int allow_ofs_delta;
 static struct pack_idx_option pack_idx_opts;
 static const char *base_name;
@@ -63,6 +84,7 @@ static unsigned long pack_size_limit;
 static int depth = 50;
 static int delta_search_threads;
 static int pack_to_stdout;
+static int thin;
 static int num_preferred_base;
 static struct progress *progress_state;
 
@@ -77,8 +99,10 @@ static uint16_t write_bitmap_options;
 
 static int exclude_promisor_objects;
 
+static int use_delta_islands;
+
 static unsigned long delta_cache_size = 0;
-static unsigned long max_delta_cache_size = 256 * 1024 * 1024;
+static unsigned long max_delta_cache_size = DEFAULT_DELTA_CACHE_SIZE;
 static unsigned long cache_max_small_delta_size = 1000;
 
 static unsigned long window_memory_limit = 0;
@@ -122,18 +146,23 @@ static void *get_delta(struct object_entry *entry)
        void *buf, *base_buf, *delta_buf;
        enum object_type type;
 
-       buf = read_sha1_file(entry->idx.oid.hash, &type, &size);
+       buf = read_object_file(&entry->idx.oid, &type, &size);
        if (!buf)
-               die("unable to read %s", oid_to_hex(&entry->idx.oid));
-       base_buf = read_sha1_file(entry->delta->idx.oid.hash, &type,
-                                 &base_size);
+               die(_("unable to read %s"), oid_to_hex(&entry->idx.oid));
+       base_buf = read_object_file(&DELTA(entry)->idx.oid, &type,
+                                   &base_size);
        if (!base_buf)
                die("unable to read %s",
-                   oid_to_hex(&entry->delta->idx.oid));
+                   oid_to_hex(&DELTA(entry)->idx.oid));
        delta_buf = diff_delta(base_buf, base_size,
                               buf, size, &delta_size, 0);
-       if (!delta_buf || delta_size != entry->delta_size)
-               die("delta size changed");
+       /*
+        * We succesfully computed this delta once but dropped it for
+        * memory reasons. Something is very wrong if this time we
+        * recompute and create a different delta.
+        */
+       if (!delta_buf || delta_size != DELTA_SIZE(entry))
+               BUG("delta size changed");
        free(buf);
        free(base_buf);
        return delta_buf;
@@ -263,15 +292,15 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
        enum object_type type;
        void *buf;
        struct git_istream *st = NULL;
+       const unsigned hashsz = the_hash_algo->rawsz;
 
        if (!usable_delta) {
-               if (entry->type == OBJ_BLOB &&
-                   entry->size > big_file_threshold &&
-                   (st = open_istream(entry->idx.oid.hash, &type, &size, NULL)) != NULL)
+               if (oe_type(entry) == OBJ_BLOB &&
+                   oe_size_greater_than(&to_pack, entry, big_file_threshold) &&
+                   (st = open_istream(&entry->idx.oid, &type, &size, NULL)) != NULL)
                        buf = NULL;
                else {
-                       buf = read_sha1_file(entry->idx.oid.hash, &type,
-                                            &size);
+                       buf = read_object_file(&entry->idx.oid, &type, &size);
                        if (!buf)
                                die(_("unable to read %s"),
                                    oid_to_hex(&entry->idx.oid));
@@ -283,15 +312,15 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
                FREE_AND_NULL(entry->delta_data);
                entry->z_delta_size = 0;
        } else if (entry->delta_data) {
-               size = entry->delta_size;
+               size = DELTA_SIZE(entry);
                buf = entry->delta_data;
                entry->delta_data = NULL;
-               type = (allow_ofs_delta && entry->delta->idx.offset) ?
+               type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
                        OBJ_OFS_DELTA : OBJ_REF_DELTA;
        } else {
                buf = get_delta(entry);
-               size = entry->delta_size;
-               type = (allow_ofs_delta && entry->delta->idx.offset) ?
+               size = DELTA_SIZE(entry);
+               type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
                        OBJ_OFS_DELTA : OBJ_REF_DELTA;
        }
 
@@ -315,12 +344,12 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
                 * encoding of the relative offset for the delta
                 * base from this object's position in the pack.
                 */
-               off_t ofs = entry->idx.offset - entry->delta->idx.offset;
+               off_t ofs = entry->idx.offset - DELTA(entry)->idx.offset;
                unsigned pos = sizeof(dheader) - 1;
                dheader[pos] = ofs & 127;
                while (ofs >>= 7)
                        dheader[--pos] = 128 | (--ofs & 127);
-               if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+               if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
@@ -332,19 +361,19 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
        } else if (type == OBJ_REF_DELTA) {
                /*
                 * Deltas with a base reference contain
-                * an additional 20 bytes for the base sha1.
+                * additional bytes for the base object ID.
                 */
-               if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+               if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
                        return 0;
                }
                hashwrite(f, header, hdrlen);
-               hashwrite(f, entry->delta->idx.oid.hash, 20);
-               hdrlen += 20;
+               hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz);
+               hdrlen += hashsz;
        } else {
-               if (limit && hdrlen + datalen + 20 >= limit) {
+               if (limit && hdrlen + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
@@ -367,28 +396,30 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
 static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
                                unsigned long limit, int usable_delta)
 {
-       struct packed_git *p = entry->in_pack;
+       struct packed_git *p = IN_PACK(entry);
        struct pack_window *w_curs = NULL;
        struct revindex_entry *revidx;
        off_t offset;
-       enum object_type type = entry->type;
+       enum object_type type = oe_type(entry);
        off_t datalen;
        unsigned char header[MAX_PACK_OBJECT_HEADER],
                      dheader[MAX_PACK_OBJECT_HEADER];
        unsigned hdrlen;
+       const unsigned hashsz = the_hash_algo->rawsz;
+       unsigned long entry_size = SIZE(entry);
 
-       if (entry->delta)
-               type = (allow_ofs_delta && entry->delta->idx.offset) ?
+       if (DELTA(entry))
+               type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
                        OBJ_OFS_DELTA : OBJ_REF_DELTA;
        hdrlen = encode_in_pack_object_header(header, sizeof(header),
-                                             type, entry->size);
+                                             type, entry_size);
 
        offset = entry->in_pack_offset;
        revidx = find_pack_revindex(p, offset);
        datalen = revidx[1].offset - offset;
        if (!pack_to_stdout && p->index_version > 1 &&
            check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
-               error("bad packed object CRC for %s",
+               error(_("bad packed object CRC for %s"),
                      oid_to_hex(&entry->idx.oid));
                unuse_pack(&w_curs);
                return write_no_reuse_object(f, entry, limit, usable_delta);
@@ -398,20 +429,20 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
        datalen -= entry->in_pack_header_size;
 
        if (!pack_to_stdout && p->index_version == 1 &&
-           check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
-               error("corrupt packed object for %s",
+           check_pack_inflate(p, &w_curs, offset, datalen, entry_size)) {
+               error(_("corrupt packed object for %s"),
                      oid_to_hex(&entry->idx.oid));
                unuse_pack(&w_curs);
                return write_no_reuse_object(f, entry, limit, usable_delta);
        }
 
        if (type == OBJ_OFS_DELTA) {
-               off_t ofs = entry->idx.offset - entry->delta->idx.offset;
+               off_t ofs = entry->idx.offset - DELTA(entry)->idx.offset;
                unsigned pos = sizeof(dheader) - 1;
                dheader[pos] = ofs & 127;
                while (ofs >>= 7)
                        dheader[--pos] = 128 | (--ofs & 127);
-               if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+               if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
@@ -420,16 +451,16 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
                hdrlen += sizeof(dheader) - pos;
                reused_delta++;
        } else if (type == OBJ_REF_DELTA) {
-               if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+               if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
                hashwrite(f, header, hdrlen);
-               hashwrite(f, entry->delta->idx.oid.hash, 20);
-               hdrlen += 20;
+               hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz);
+               hdrlen += hashsz;
                reused_delta++;
        } else {
-               if (limit && hdrlen + datalen + 20 >= limit) {
+               if (limit && hdrlen + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
@@ -465,28 +496,29 @@ static off_t write_object(struct hashfile *f,
        else
                limit = pack_size_limit - write_offset;
 
-       if (!entry->delta)
+       if (!DELTA(entry))
                usable_delta = 0;       /* no delta */
        else if (!pack_size_limit)
               usable_delta = 1;        /* unlimited packfile */
-       else if (entry->delta->idx.offset == (off_t)-1)
+       else if (DELTA(entry)->idx.offset == (off_t)-1)
                usable_delta = 0;       /* base was written to another pack */
-       else if (entry->delta->idx.offset)
+       else if (DELTA(entry)->idx.offset)
                usable_delta = 1;       /* base already exists in this pack */
        else
                usable_delta = 0;       /* base could end up in another pack */
 
        if (!reuse_object)
                to_reuse = 0;   /* explicit */
-       else if (!entry->in_pack)
+       else if (!IN_PACK(entry))
                to_reuse = 0;   /* can't reuse what we don't have */
-       else if (entry->type == OBJ_REF_DELTA || entry->type == OBJ_OFS_DELTA)
+       else if (oe_type(entry) == OBJ_REF_DELTA ||
+                oe_type(entry) == OBJ_OFS_DELTA)
                                /* check_object() decided it for us ... */
                to_reuse = usable_delta;
                                /* ... but pack split may override that */
-       else if (entry->type != entry->in_pack_type)
+       else if (oe_type(entry) != entry->in_pack_type)
                to_reuse = 0;   /* pack has delta which is unusable */
-       else if (entry->delta)
+       else if (DELTA(entry))
                to_reuse = 0;   /* we want to pack afresh */
        else
                to_reuse = 1;   /* we have it in-pack undeltified,
@@ -529,7 +561,7 @@ static enum write_one_status write_one(struct hashfile *f,
         */
        recursing = (e->idx.offset == 1);
        if (recursing) {
-               warning("recursive delta detected for object %s",
+               warning(_("recursive delta detected for object %s"),
                        oid_to_hex(&e->idx.oid));
                return WRITE_ONE_RECURSIVE;
        } else if (e->idx.offset || e->preferred_base) {
@@ -538,12 +570,12 @@ static enum write_one_status write_one(struct hashfile *f,
        }
 
        /* if we are deltified, write out base object first. */
-       if (e->delta) {
+       if (DELTA(e)) {
                e->idx.offset = 1; /* now recurse */
-               switch (write_one(f, e->delta, offset)) {
+               switch (write_one(f, DELTA(e), offset)) {
                case WRITE_ONE_RECURSIVE:
                        /* we cannot depend on this one */
-                       e->delta = NULL;
+                       SET_DELTA(e, NULL);
                        break;
                default:
                        break;
@@ -563,7 +595,7 @@ static enum write_one_status write_one(struct hashfile *f,
 
        /* make sure off_t is sufficiently large not to wrap */
        if (signed_add_overflows(*offset, size))
-               die("pack too large for current definition of off_t");
+               die(_("pack too large for current definition of off_t"));
        *offset += size;
        return WRITE_ONE_WRITTEN;
 }
@@ -588,7 +620,7 @@ static inline void add_to_write_order(struct object_entry **wo,
                               unsigned int *endp,
                               struct object_entry *e)
 {
-       if (e->filled)
+       if (e->filled || oe_layer(&to_pack, e) != write_layer)
                return;
        wo[(*endp)++] = e;
        e->filled = 1;
@@ -605,34 +637,34 @@ static void add_descendants_to_write_order(struct object_entry **wo,
                        /* add this node... */
                        add_to_write_order(wo, endp, e);
                        /* all its siblings... */
-                       for (s = e->delta_sibling; s; s = s->delta_sibling) {
+                       for (s = DELTA_SIBLING(e); s; s = DELTA_SIBLING(s)) {
                                add_to_write_order(wo, endp, s);
                        }
                }
                /* drop down a level to add left subtree nodes if possible */
-               if (e->delta_child) {
+               if (DELTA_CHILD(e)) {
                        add_to_order = 1;
-                       e = e->delta_child;
+                       e = DELTA_CHILD(e);
                } else {
                        add_to_order = 0;
                        /* our sibling might have some children, it is next */
-                       if (e->delta_sibling) {
-                               e = e->delta_sibling;
+                       if (DELTA_SIBLING(e)) {
+                               e = DELTA_SIBLING(e);
                                continue;
                        }
                        /* go back to our parent node */
-                       e = e->delta;
-                       while (e && !e->delta_sibling) {
+                       e = DELTA(e);
+                       while (e && !DELTA_SIBLING(e)) {
                                /* we're on the right side of a subtree, keep
                                 * going up until we can go right again */
-                               e = e->delta;
+                               e = DELTA(e);
                        }
                        if (!e) {
                                /* done- we hit our original root node */
                                return;
                        }
                        /* pass it off to sibling at this level */
-                       e = e->delta_sibling;
+                       e = DELTA_SIBLING(e);
                }
        };
 }
@@ -643,53 +675,20 @@ static void add_family_to_write_order(struct object_entry **wo,
 {
        struct object_entry *root;
 
-       for (root = e; root->delta; root = root->delta)
+       for (root = e; DELTA(root); root = DELTA(root))
                ; /* nothing */
        add_descendants_to_write_order(wo, endp, root);
 }
 
-static struct object_entry **compute_write_order(void)
+static void compute_layer_order(struct object_entry **wo, unsigned int *wo_end)
 {
-       unsigned int i, wo_end, last_untagged;
-
-       struct object_entry **wo;
+       unsigned int i, last_untagged;
        struct object_entry *objects = to_pack.objects;
 
        for (i = 0; i < to_pack.nr_objects; i++) {
-               objects[i].tagged = 0;
-               objects[i].filled = 0;
-               objects[i].delta_child = NULL;
-               objects[i].delta_sibling = NULL;
-       }
-
-       /*
-        * Fully connect delta_child/delta_sibling network.
-        * Make sure delta_sibling is sorted in the original
-        * recency order.
-        */
-       for (i = to_pack.nr_objects; i > 0;) {
-               struct object_entry *e = &objects[--i];
-               if (!e->delta)
-                       continue;
-               /* Mark me as the first child */
-               e->delta_sibling = e->delta->delta_child;
-               e->delta->delta_child = e;
-       }
-
-       /*
-        * Mark objects that are at the tip of tags.
-        */
-       for_each_tag_ref(mark_tagged, NULL);
-
-       /*
-        * Give the objects in the original recency order until
-        * we see a tagged tip.
-        */
-       ALLOC_ARRAY(wo, to_pack.nr_objects);
-       for (i = wo_end = 0; i < to_pack.nr_objects; i++) {
                if (objects[i].tagged)
                        break;
-               add_to_write_order(wo, &wo_end, &objects[i]);
+               add_to_write_order(wo, wo_end, &objects[i]);
        }
        last_untagged = i;
 
@@ -698,38 +697,83 @@ static struct object_entry **compute_write_order(void)
         */
        for (; i < to_pack.nr_objects; i++) {
                if (objects[i].tagged)
-                       add_to_write_order(wo, &wo_end, &objects[i]);
+                       add_to_write_order(wo, wo_end, &objects[i]);
        }
 
        /*
         * And then all remaining commits and tags.
         */
        for (i = last_untagged; i < to_pack.nr_objects; i++) {
-               if (objects[i].type != OBJ_COMMIT &&
-                   objects[i].type != OBJ_TAG)
+               if (oe_type(&objects[i]) != OBJ_COMMIT &&
+                   oe_type(&objects[i]) != OBJ_TAG)
                        continue;
-               add_to_write_order(wo, &wo_end, &objects[i]);
+               add_to_write_order(wo, wo_end, &objects[i]);
        }
 
        /*
         * And then all the trees.
         */
        for (i = last_untagged; i < to_pack.nr_objects; i++) {
-               if (objects[i].type != OBJ_TREE)
+               if (oe_type(&objects[i]) != OBJ_TREE)
                        continue;
-               add_to_write_order(wo, &wo_end, &objects[i]);
+               add_to_write_order(wo, wo_end, &objects[i]);
        }
 
        /*
         * Finally all the rest in really tight order
         */
        for (i = last_untagged; i < to_pack.nr_objects; i++) {
-               if (!objects[i].filled)
-                       add_family_to_write_order(wo, &wo_end, &objects[i]);
+               if (!objects[i].filled && oe_layer(&to_pack, &objects[i]) == write_layer)
+                       add_family_to_write_order(wo, wo_end, &objects[i]);
+       }
+}
+
+static struct object_entry **compute_write_order(void)
+{
+       uint32_t max_layers = 1;
+       unsigned int i, wo_end;
+
+       struct object_entry **wo;
+       struct object_entry *objects = to_pack.objects;
+
+       for (i = 0; i < to_pack.nr_objects; i++) {
+               objects[i].tagged = 0;
+               objects[i].filled = 0;
+               SET_DELTA_CHILD(&objects[i], NULL);
+               SET_DELTA_SIBLING(&objects[i], NULL);
+       }
+
+       /*
+        * Fully connect delta_child/delta_sibling network.
+        * Make sure delta_sibling is sorted in the original
+        * recency order.
+        */
+       for (i = to_pack.nr_objects; i > 0;) {
+               struct object_entry *e = &objects[--i];
+               if (!DELTA(e))
+                       continue;
+               /* Mark me as the first child */
+               e->delta_sibling_idx = DELTA(e)->delta_child_idx;
+               SET_DELTA_CHILD(DELTA(e), e);
        }
 
+       /*
+        * Mark objects that are at the tip of tags.
+        */
+       for_each_tag_ref(mark_tagged, NULL);
+
+       if (use_delta_islands)
+               max_layers = compute_pack_layers(&to_pack);
+
+       ALLOC_ARRAY(wo, to_pack.nr_objects);
+       wo_end = 0;
+
+       for (; write_layer < max_layers; ++write_layer)
+               compute_layer_order(wo, &wo_end);
+
        if (wo_end != to_pack.nr_objects)
-               die("ordered %u objects, expected %"PRIu32, wo_end, to_pack.nr_objects);
+               die(_("ordered %u objects, expected %"PRIu32),
+                   wo_end, to_pack.nr_objects);
 
        return wo;
 }
@@ -741,18 +785,18 @@ static off_t write_reused_pack(struct hashfile *f)
        int fd;
 
        if (!is_pack_valid(reuse_packfile))
-               die("packfile is invalid: %s", reuse_packfile->pack_name);
+               die(_("packfile is invalid: %s"), reuse_packfile->pack_name);
 
        fd = git_open(reuse_packfile->pack_name);
        if (fd < 0)
-               die_errno("unable to open packfile for reuse: %s",
+               die_errno(_("unable to open packfile for reuse: %s"),
                          reuse_packfile->pack_name);
 
        if (lseek(fd, sizeof(struct pack_header), SEEK_SET) == -1)
-               die_errno("unable to seek in reused packfile");
+               die_errno(_("unable to seek in reused packfile"));
 
        if (reuse_packfile_offset < 0)
-               reuse_packfile_offset = reuse_packfile->pack_size - 20;
+               reuse_packfile_offset = reuse_packfile->pack_size - the_hash_algo->rawsz;
 
        total = to_write = reuse_packfile_offset - sizeof(struct pack_header);
 
@@ -760,7 +804,7 @@ static off_t write_reused_pack(struct hashfile *f)
                int read_pack = xread(fd, buffer, sizeof(buffer));
 
                if (read_pack <= 0)
-                       die_errno("unable to read from reused packfile");
+                       die_errno(_("unable to read from reused packfile"));
 
                if (read_pack > to_write)
                        read_pack = to_write;
@@ -837,11 +881,11 @@ static void write_pack_file(void)
                 * If so, rewrite it like in fast-import
                 */
                if (pack_to_stdout) {
-                       hashclose(f, oid.hash, CSUM_CLOSE);
+                       finalize_hashfile(f, oid.hash, CSUM_HASH_IN_STREAM | CSUM_CLOSE);
                } else if (nr_written == nr_remaining) {
-                       hashclose(f, oid.hash, CSUM_FSYNC);
+                       finalize_hashfile(f, oid.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
                } else {
-                       int fd = hashclose(f, oid.hash, 0);
+                       int fd = finalize_hashfile(f, oid.hash, 0);
                        fixup_pack_header_footer(fd, oid.hash, pack_tmp_name,
                                                 nr_written, oid.hash, offset);
                        close(fd);
@@ -863,7 +907,7 @@ static void write_pack_file(void)
                         * to preserve this property.
                         */
                        if (stat(pack_tmp_name, &st) < 0) {
-                               warning_errno("failed to stat %s", pack_tmp_name);
+                               warning_errno(_("failed to stat %s"), pack_tmp_name);
                        } else if (!last_mtime) {
                                last_mtime = st.st_mtime;
                        } else {
@@ -871,14 +915,15 @@ static void write_pack_file(void)
                                utb.actime = st.st_atime;
                                utb.modtime = --last_mtime;
                                if (utime(pack_tmp_name, &utb) < 0)
-                                       warning_errno("failed utime() on %s", pack_tmp_name);
+                                       warning_errno(_("failed utime() on %s"), pack_tmp_name);
                        }
 
                        strbuf_addf(&tmpname, "%s-", base_name);
 
                        if (write_bitmap_index) {
                                bitmap_writer_set_checksum(oid.hash);
-                               bitmap_writer_build_type_index(written_list, nr_written);
+                               bitmap_writer_build_type_index(
+                                       &to_pack, written_list, nr_written);
                        }
 
                        finish_tmp_packfile(&tmpname, pack_tmp_name,
@@ -915,8 +960,8 @@ static void write_pack_file(void)
        free(write_order);
        stop_progress(&progress_state);
        if (written != nr_result)
-               die("wrote %"PRIu32" objects while expecting %"PRIu32,
-                       written, nr_result);
+               die(_("wrote %"PRIu32" objects while expecting %"PRIu32),
+                   written, nr_result);
 }
 
 static int no_try_delta(const char *path)
@@ -925,8 +970,7 @@ static int no_try_delta(const char *path)
 
        if (!check)
                check = attr_check_initl("delta", NULL);
-       if (git_check_attr(path, check))
-               return 0;
+       git_check_attr(&the_index, path, check);
        if (ATTR_FALSE(check->items[0].value))
                return 1;
        return 0;
@@ -982,13 +1026,16 @@ static int want_found_object(int exclude, struct packed_git *p)
         * Otherwise, we signal "-1" at the end to tell the caller that we do
         * not know either way, and it needs to check more packs.
         */
-       if (!ignore_packed_keep &&
+       if (!ignore_packed_keep_on_disk &&
+           !ignore_packed_keep_in_core &&
            (!local || !have_non_local_packs))
                return 1;
 
        if (local && !p->pack_local)
                return 0;
-       if (ignore_packed_keep && p->pack_local && p->pack_keep)
+       if (p->pack_local &&
+           ((ignore_packed_keep_on_disk && p->pack_keep) ||
+            (ignore_packed_keep_in_core && p->pack_keep_in_core)))
                return 0;
 
        /* we don't know yet; keep looking for more packs */
@@ -1011,8 +1058,9 @@ static int want_object_in_pack(const struct object_id *oid,
 {
        int want;
        struct list_head *pos;
+       struct multi_pack_index *m;
 
-       if (!exclude && local && has_loose_object_nonlocal(oid->hash))
+       if (!exclude && local && has_loose_object_nonlocal(oid))
                return 0;
 
        /*
@@ -1026,7 +1074,32 @@ static int want_object_in_pack(const struct object_id *oid,
                        return want;
        }
 
-       list_for_each(pos, &packed_git_mru) {
+       for (m = get_multi_pack_index(the_repository); m; m = m->next) {
+               struct pack_entry e;
+               if (fill_midx_entry(oid, &e, m)) {
+                       struct packed_git *p = e.p;
+                       off_t offset;
+
+                       if (p == *found_pack)
+                               offset = *found_offset;
+                       else
+                               offset = find_pack_entry_one(oid->hash, p);
+
+                       if (offset) {
+                               if (!*found_pack) {
+                                       if (!is_pack_valid(p))
+                                               continue;
+                                       *found_offset = offset;
+                                       *found_pack = p;
+                               }
+                               want = want_found_object(exclude, p);
+                               if (want != -1)
+                                       return want;
+                       }
+               }
+       }
+
+       list_for_each(pos, get_packed_git_mru(the_repository)) {
                struct packed_git *p = list_entry(pos, struct packed_git, mru);
                off_t offset;
 
@@ -1044,7 +1117,8 @@ static int want_object_in_pack(const struct object_id *oid,
                        }
                        want = want_found_object(exclude, p);
                        if (!exclude && want > 0)
-                               list_move(&p->mru, &packed_git_mru);
+                               list_move(&p->mru,
+                                         get_packed_git_mru(the_repository));
                        if (want != -1)
                                return want;
                }
@@ -1066,14 +1140,13 @@ static void create_object_entry(const struct object_id *oid,
 
        entry = packlist_alloc(&to_pack, oid->hash, index_pos);
        entry->hash = hash;
-       if (type)
-               entry->type = type;
+       oe_set_type(entry, type);
        if (exclude)
                entry->preferred_base = 1;
        else
                nr_result++;
        if (found_pack) {
-               entry->in_pack = found_pack;
+               oe_set_in_pack(&to_pack, entry, found_pack);
                entry->in_pack_offset = found_offset;
        }
 
@@ -1091,6 +1164,8 @@ static int add_object_entry(const struct object_id *oid, enum object_type type,
        off_t found_offset = 0;
        uint32_t index_pos;
 
+       display_progress(progress_state, ++nr_seen);
+
        if (have_duplicate_entry(oid, exclude, &index_pos))
                return 0;
 
@@ -1106,8 +1181,6 @@ static int add_object_entry(const struct object_id *oid, enum object_type type,
        create_object_entry(oid, type, pack_name_hash(name),
                            exclude, name && no_try_delta(name),
                            index_pos, found_pack, found_offset);
-
-       display_progress(progress_state, nr_result);
        return 1;
 }
 
@@ -1118,6 +1191,8 @@ static int add_object_entry_from_bitmap(const struct object_id *oid,
 {
        uint32_t index_pos;
 
+       display_progress(progress_state, ++nr_seen);
+
        if (have_duplicate_entry(oid, 0, &index_pos))
                return 0;
 
@@ -1125,8 +1200,6 @@ static int add_object_entry_from_bitmap(const struct object_id *oid,
                return 0;
 
        create_object_entry(oid, type, name_hash, 0, 0, index_pos, pack, offset);
-
-       display_progress(progress_state, nr_result);
        return 1;
 }
 
@@ -1174,7 +1247,7 @@ static struct pbase_tree_cache *pbase_tree_get(const struct object_id *oid)
         */
        for (neigh = 0; neigh < 8; neigh++) {
                ent = pbase_tree_cache[my_ix];
-               if (ent && !oidcmp(&ent->oid, oid)) {
+               if (ent && oideq(&ent->oid, oid)) {
                        ent->ref++;
                        return ent;
                }
@@ -1190,7 +1263,7 @@ static struct pbase_tree_cache *pbase_tree_get(const struct object_id *oid)
        /* Did not find one.  Either we got a bogus request or
         * we need to read and perhaps cache.
         */
-       data = read_sha1_file(oid->hash, &type, &size);
+       data = read_object_file(oid, &type, &size);
        if (!data)
                return NULL;
        if (type != OBJ_TREE) {
@@ -1351,12 +1424,12 @@ static void add_preferred_base(struct object_id *oid)
        if (window <= num_preferred_base++)
                return;
 
-       data = read_object_with_reference(oid->hash, tree_type, &size, tree_oid.hash);
+       data = read_object_with_reference(oid, tree_type, &size, &tree_oid);
        if (!data)
                return;
 
        for (it = pbase_tree; it; it = it->next) {
-               if (!oidcmp(&it->pcache.oid, &tree_oid)) {
+               if (oideq(&it->pcache.oid, &tree_oid)) {
                        free(data);
                        return;
                }
@@ -1396,10 +1469,63 @@ static void cleanup_preferred_base(void)
        done_pbase_paths_num = done_pbase_paths_alloc = 0;
 }
 
+/*
+ * Return 1 iff the object specified by "delta" can be sent
+ * literally as a delta against the base in "base_sha1". If
+ * so, then *base_out will point to the entry in our packing
+ * list, or NULL if we must use the external-base list.
+ *
+ * Depth value does not matter - find_deltas() will
+ * never consider reused delta as the base object to
+ * deltify other objects against, in order to avoid
+ * circular deltas.
+ */
+static int can_reuse_delta(const unsigned char *base_sha1,
+                          struct object_entry *delta,
+                          struct object_entry **base_out)
+{
+       struct object_entry *base;
+
+       if (!base_sha1)
+               return 0;
+
+       /*
+        * First see if we're already sending the base (or it's explicitly in
+        * our "excluded" list).
+        */
+       base = packlist_find(&to_pack, base_sha1, NULL);
+       if (base) {
+               if (!in_same_island(&delta->idx.oid, &base->idx.oid))
+                       return 0;
+               *base_out = base;
+               return 1;
+       }
+
+       /*
+        * Otherwise, reachability bitmaps may tell us if the receiver has it,
+        * even if it was buried too deep in history to make it into the
+        * packing list.
+        */
+       if (thin && bitmap_has_sha1_in_uninteresting(bitmap_git, base_sha1)) {
+               if (use_delta_islands) {
+                       struct object_id base_oid;
+                       hashcpy(base_oid.hash, base_sha1);
+                       if (!in_same_island(&delta->idx.oid, &base_oid))
+                               return 0;
+               }
+               *base_out = NULL;
+               return 1;
+       }
+
+       return 0;
+}
+
 static void check_object(struct object_entry *entry)
 {
-       if (entry->in_pack) {
-               struct packed_git *p = entry->in_pack;
+       unsigned long canonical_size;
+
+       if (IN_PACK(entry)) {
+               struct packed_git *p = IN_PACK(entry);
                struct pack_window *w_curs = NULL;
                const unsigned char *base_ref = NULL;
                struct object_entry *base_entry;
@@ -1407,6 +1533,8 @@ static void check_object(struct object_entry *entry)
                unsigned long avail;
                off_t ofs;
                unsigned char *buf, c;
+               enum object_type type;
+               unsigned long in_pack_size;
 
                buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
 
@@ -1415,11 +1543,15 @@ static void check_object(struct object_entry *entry)
                 * since non-delta representations could still be reused.
                 */
                used = unpack_object_header_buffer(buf, avail,
-                                                  &entry->in_pack_type,
-                                                  &entry->size);
+                                                  &type,
+                                                  &in_pack_size);
                if (used == 0)
                        goto give_up;
 
+               if (type < 0)
+                       BUG("invalid type %d", type);
+               entry->in_pack_type = type;
+
                /*
                 * Determine if this is a delta and if so whether we can
                 * reuse it or not.  Otherwise let's find out as cheaply as
@@ -1428,9 +1560,10 @@ static void check_object(struct object_entry *entry)
                switch (entry->in_pack_type) {
                default:
                        /* Not a delta hence we've already got all we need. */
-                       entry->type = entry->in_pack_type;
+                       oe_set_type(entry, entry->in_pack_type);
+                       SET_SIZE(entry, in_pack_size);
                        entry->in_pack_header_size = used;
-                       if (entry->type < OBJ_COMMIT || entry->type > OBJ_BLOB)
+                       if (oe_type(entry) < OBJ_COMMIT || oe_type(entry) > OBJ_BLOB)
                                goto give_up;
                        unuse_pack(&w_curs);
                        return;
@@ -1438,7 +1571,7 @@ static void check_object(struct object_entry *entry)
                        if (reuse_delta && !entry->preferred_base)
                                base_ref = use_pack(p, &w_curs,
                                                entry->in_pack_offset + used, NULL);
-                       entry->in_pack_header_size = used + 20;
+                       entry->in_pack_header_size = used + the_hash_algo->rawsz;
                        break;
                case OBJ_OFS_DELTA:
                        buf = use_pack(p, &w_curs,
@@ -1449,7 +1582,7 @@ static void check_object(struct object_entry *entry)
                        while (c & 128) {
                                ofs += 1;
                                if (!ofs || MSB(ofs, 7)) {
-                                       error("delta base offset overflow in pack for %s",
+                                       error(_("delta base offset overflow in pack for %s"),
                                              oid_to_hex(&entry->idx.oid));
                                        goto give_up;
                                }
@@ -1458,7 +1591,7 @@ static void check_object(struct object_entry *entry)
                        }
                        ofs = entry->in_pack_offset - ofs;
                        if (ofs <= 0 || ofs >= entry->in_pack_offset) {
-                               error("delta base offset out of bound for %s",
+                               error(_("delta base offset out of bound for %s"),
                                      oid_to_hex(&entry->idx.oid));
                                goto give_up;
                        }
@@ -1473,36 +1606,36 @@ static void check_object(struct object_entry *entry)
                        break;
                }
 
-               if (base_ref && (base_entry = packlist_find(&to_pack, base_ref, NULL))) {
-                       /*
-                        * If base_ref was set above that means we wish to
-                        * reuse delta data, and we even found that base
-                        * in the list of objects we want to pack. Goodie!
-                        *
-                        * Depth value does not matter - find_deltas() will
-                        * never consider reused delta as the base object to
-                        * deltify other objects against, in order to avoid
-                        * circular deltas.
-                        */
-                       entry->type = entry->in_pack_type;
-                       entry->delta = base_entry;
-                       entry->delta_size = entry->size;
-                       entry->delta_sibling = base_entry->delta_child;
-                       base_entry->delta_child = entry;
+               if (can_reuse_delta(base_ref, entry, &base_entry)) {
+                       oe_set_type(entry, entry->in_pack_type);
+                       SET_SIZE(entry, in_pack_size); /* delta size */
+                       SET_DELTA_SIZE(entry, in_pack_size);
+
+                       if (base_entry) {
+                               SET_DELTA(entry, base_entry);
+                               entry->delta_sibling_idx = base_entry->delta_child_idx;
+                               SET_DELTA_CHILD(base_entry, entry);
+                       } else {
+                               SET_DELTA_EXT(entry, base_ref);
+                       }
+
                        unuse_pack(&w_curs);
                        return;
                }
 
-               if (entry->type) {
+               if (oe_type(entry)) {
+                       off_t delta_pos;
+
                        /*
                         * This must be a delta and we already know what the
                         * final object type is.  Let's extract the actual
                         * object size from the delta header.
                         */
-                       entry->size = get_size_from_delta(p, &w_curs,
-                                       entry->in_pack_offset + entry->in_pack_header_size);
-                       if (entry->size == 0)
+                       delta_pos = entry->in_pack_offset + entry->in_pack_header_size;
+                       canonical_size = get_size_from_delta(p, &w_curs, delta_pos);
+                       if (canonical_size == 0)
                                goto give_up;
+                       SET_SIZE(entry, canonical_size);
                        unuse_pack(&w_curs);
                        return;
                }
@@ -1516,27 +1649,34 @@ static void check_object(struct object_entry *entry)
                unuse_pack(&w_curs);
        }
 
-       entry->type = sha1_object_info(entry->idx.oid.hash, &entry->size);
-       /*
-        * The error condition is checked in prepare_pack().  This is
-        * to permit a missing preferred base object to be ignored
-        * as a preferred base.  Doing so can result in a larger
-        * pack file, but the transfer will still take place.
-        */
+       oe_set_type(entry,
+                   oid_object_info(the_repository, &entry->idx.oid, &canonical_size));
+       if (entry->type_valid) {
+               SET_SIZE(entry, canonical_size);
+       } else {
+               /*
+                * Bad object type is checked in prepare_pack().  This is
+                * to permit a missing preferred base object to be ignored
+                * as a preferred base.  Doing so can result in a larger
+                * pack file, but the transfer will still take place.
+                */
+       }
 }
 
 static int pack_offset_sort(const void *_a, const void *_b)
 {
        const struct object_entry *a = *(struct object_entry **)_a;
        const struct object_entry *b = *(struct object_entry **)_b;
+       const struct packed_git *a_in_pack = IN_PACK(a);
+       const struct packed_git *b_in_pack = IN_PACK(b);
 
        /* avoid filesystem trashing with loose objects */
-       if (!a->in_pack && !b->in_pack)
+       if (!a_in_pack && !b_in_pack)
                return oidcmp(&a->idx.oid, &b->idx.oid);
 
-       if (a->in_pack < b->in_pack)
+       if (a_in_pack < b_in_pack)
                return -1;
-       if (a->in_pack > b->in_pack)
+       if (a_in_pack > b_in_pack)
                return 1;
        return a->in_pack_offset < b->in_pack_offset ? -1 :
                        (a->in_pack_offset > b->in_pack_offset);
@@ -1557,30 +1697,37 @@ static int pack_offset_sort(const void *_a, const void *_b)
  */
 static void drop_reused_delta(struct object_entry *entry)
 {
-       struct object_entry **p = &entry->delta->delta_child;
+       unsigned *idx = &to_pack.objects[entry->delta_idx - 1].delta_child_idx;
        struct object_info oi = OBJECT_INFO_INIT;
+       enum object_type type;
+       unsigned long size;
 
-       while (*p) {
-               if (*p == entry)
-                       *p = (*p)->delta_sibling;
+       while (*idx) {
+               struct object_entry *oe = &to_pack.objects[*idx - 1];
+
+               if (oe == entry)
+                       *idx = oe->delta_sibling_idx;
                else
-                       p = &(*p)->delta_sibling;
+                       idx = &oe->delta_sibling_idx;
        }
-       entry->delta = NULL;
+       SET_DELTA(entry, NULL);
        entry->depth = 0;
 
-       oi.sizep = &entry->size;
-       oi.typep = &entry->type;
-       if (packed_object_info(entry->in_pack, entry->in_pack_offset, &oi) < 0) {
+       oi.sizep = &size;
+       oi.typep = &type;
+       if (packed_object_info(the_repository, IN_PACK(entry), entry->in_pack_offset, &oi) < 0) {
                /*
                 * We failed to get the info from this pack for some reason;
                 * fall back to sha1_object_info, which may find another copy.
-                * And if that fails, the error will be recorded in entry->type
+                * And if that fails, the error will be recorded in oe_type(entry)
                 * and dealt with in prepare_pack().
                 */
-               entry->type = sha1_object_info(entry->idx.oid.hash,
-                                              &entry->size);
+               oe_set_type(entry,
+                           oid_object_info(the_repository, &entry->idx.oid, &size));
+       } else {
+               oe_set_type(entry, type);
        }
+       SET_SIZE(entry, size);
 }
 
 /*
@@ -1604,7 +1751,7 @@ static void break_delta_chains(struct object_entry *entry)
 
        for (cur = entry, total_depth = 0;
             cur;
-            cur = cur->delta, total_depth++) {
+            cur = DELTA(cur), total_depth++) {
                if (cur->dfs_state == DFS_DONE) {
                        /*
                         * We've already seen this object and know it isn't
@@ -1621,7 +1768,7 @@ static void break_delta_chains(struct object_entry *entry)
                 * is a bug.
                 */
                if (cur->dfs_state != DFS_NONE)
-                       die("BUG: confusing delta dfs state in first pass: %d",
+                       BUG("confusing delta dfs state in first pass: %d",
                            cur->dfs_state);
 
                /*
@@ -1629,7 +1776,7 @@ static void break_delta_chains(struct object_entry *entry)
                 * it's not a delta, we're done traversing, but we'll mark it
                 * done to save time on future traversals.
                 */
-               if (!cur->delta) {
+               if (!DELTA(cur)) {
                        cur->dfs_state = DFS_DONE;
                        break;
                }
@@ -1652,7 +1799,7 @@ static void break_delta_chains(struct object_entry *entry)
                 * We keep all commits in the chain that we examined.
                 */
                cur->dfs_state = DFS_ACTIVE;
-               if (cur->delta->dfs_state == DFS_ACTIVE) {
+               if (DELTA(cur)->dfs_state == DFS_ACTIVE) {
                        drop_reused_delta(cur);
                        cur->dfs_state = DFS_DONE;
                        break;
@@ -1667,7 +1814,7 @@ static void break_delta_chains(struct object_entry *entry)
         * an extra "next" pointer to keep going after we reset cur->delta.
         */
        for (cur = entry; cur; cur = next) {
-               next = cur->delta;
+               next = DELTA(cur);
 
                /*
                 * We should have a chain of zero or more ACTIVE states down to
@@ -1678,7 +1825,7 @@ static void break_delta_chains(struct object_entry *entry)
                if (cur->dfs_state == DFS_DONE)
                        break;
                else if (cur->dfs_state != DFS_ACTIVE)
-                       die("BUG: confusing delta dfs state in second pass: %d",
+                       BUG("confusing delta dfs state in second pass: %d",
                            cur->dfs_state);
 
                /*
@@ -1712,6 +1859,10 @@ static void get_object_details(void)
        uint32_t i;
        struct object_entry **sorted_by_offset;
 
+       if (progress)
+               progress_state = start_progress(_("Counting objects"),
+                                               to_pack.nr_objects);
+
        sorted_by_offset = xcalloc(to_pack.nr_objects, sizeof(struct object_entry *));
        for (i = 0; i < to_pack.nr_objects; i++)
                sorted_by_offset[i] = to_pack.objects + i;
@@ -1720,9 +1871,12 @@ static void get_object_details(void)
        for (i = 0; i < to_pack.nr_objects; i++) {
                struct object_entry *entry = sorted_by_offset[i];
                check_object(entry);
-               if (big_file_threshold < entry->size)
+               if (entry->type_valid &&
+                   oe_size_greater_than(&to_pack, entry, big_file_threshold))
                        entry->no_try_delta = 1;
+               display_progress(progress_state, i + 1);
        }
+       stop_progress(&progress_state);
 
        /*
         * This must happen in a second pass, since we rely on the delta
@@ -1747,10 +1901,14 @@ static int type_size_sort(const void *_a, const void *_b)
 {
        const struct object_entry *a = *(struct object_entry **)_a;
        const struct object_entry *b = *(struct object_entry **)_b;
+       enum object_type a_type = oe_type(a);
+       enum object_type b_type = oe_type(b);
+       unsigned long a_size = SIZE(a);
+       unsigned long b_size = SIZE(b);
 
-       if (a->type > b->type)
+       if (a_type > b_type)
                return -1;
-       if (a->type < b->type)
+       if (a_type < b_type)
                return 1;
        if (a->hash > b->hash)
                return -1;
@@ -1760,9 +1918,14 @@ static int type_size_sort(const void *_a, const void *_b)
                return -1;
        if (a->preferred_base < b->preferred_base)
                return 1;
-       if (a->size > b->size)
+       if (use_delta_islands) {
+               int island_cmp = island_delta_cmp(&a->idx.oid, &b->idx.oid);
+               if (island_cmp)
+                       return island_cmp;
+       }
+       if (a_size > b_size)
                return -1;
-       if (a->size < b->size)
+       if (a_size < b_size)
                return 1;
        return a < b ? -1 : (a > b);  /* newest first */
 }
@@ -1792,18 +1955,30 @@ static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
 
 #ifndef NO_PTHREADS
 
+/* Protect access to object database */
 static pthread_mutex_t read_mutex;
 #define read_lock()            pthread_mutex_lock(&read_mutex)
 #define read_unlock()          pthread_mutex_unlock(&read_mutex)
 
+/* Protect delta_cache_size */
 static pthread_mutex_t cache_mutex;
 #define cache_lock()           pthread_mutex_lock(&cache_mutex)
 #define cache_unlock()         pthread_mutex_unlock(&cache_mutex)
 
+/*
+ * Protect object list partitioning (e.g. struct thread_param) and
+ * progress_state
+ */
 static pthread_mutex_t progress_mutex;
 #define progress_lock()                pthread_mutex_lock(&progress_mutex)
 #define progress_unlock()      pthread_mutex_unlock(&progress_mutex)
 
+/*
+ * Access to struct object_entry is unprotected since each thread owns
+ * a portion of the main object list. Just don't access object entries
+ * ahead in the list because they can be stolen and would need
+ * progress_mutex for protection.
+ */
 #else
 
 #define read_lock()            (void)0
@@ -1815,6 +1990,46 @@ static pthread_mutex_t progress_mutex;
 
 #endif
 
+/*
+ * Return the size of the object without doing any delta
+ * reconstruction (so non-deltas are true object sizes, but deltas
+ * return the size of the delta data).
+ */
+unsigned long oe_get_size_slow(struct packing_data *pack,
+                              const struct object_entry *e)
+{
+       struct packed_git *p;
+       struct pack_window *w_curs;
+       unsigned char *buf;
+       enum object_type type;
+       unsigned long used, avail, size;
+
+       if (e->type_ != OBJ_OFS_DELTA && e->type_ != OBJ_REF_DELTA) {
+               read_lock();
+               if (oid_object_info(the_repository, &e->idx.oid, &size) < 0)
+                       die(_("unable to get size of %s"),
+                           oid_to_hex(&e->idx.oid));
+               read_unlock();
+               return size;
+       }
+
+       p = oe_in_pack(pack, e);
+       if (!p)
+               BUG("when e->type is a delta, it must belong to a pack");
+
+       read_lock();
+       w_curs = NULL;
+       buf = use_pack(p, &w_curs, e->in_pack_offset, &avail);
+       used = unpack_object_header_buffer(buf, avail, &type, &size);
+       if (used == 0)
+               die(_("unable to parse object header of %s"),
+                   oid_to_hex(&e->idx.oid));
+
+       unuse_pack(&w_curs);
+       read_unlock();
+       return size;
+}
+
 static int try_delta(struct unpacked *trg, struct unpacked *src,
                     unsigned max_depth, unsigned long *mem_usage)
 {
@@ -1826,7 +2041,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
        void *delta_buf;
 
        /* Don't bother doing diffs between different types */
-       if (trg_entry->type != src_entry->type)
+       if (oe_type(trg_entry) != oe_type(src_entry))
                return -1;
 
        /*
@@ -1837,8 +2052,8 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
         * it, we will still save the transfer cost, as we already know
         * the other side has it and we won't send src_entry at all.
         */
-       if (reuse_delta && trg_entry->in_pack &&
-           trg_entry->in_pack == src_entry->in_pack &&
+       if (reuse_delta && IN_PACK(trg_entry) &&
+           IN_PACK(trg_entry) == IN_PACK(src_entry) &&
            !src_entry->preferred_base &&
            trg_entry->in_pack_type != OBJ_REF_DELTA &&
            trg_entry->in_pack_type != OBJ_OFS_DELTA)
@@ -1849,50 +2064,51 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
                return 0;
 
        /* Now some size filtering heuristics. */
-       trg_size = trg_entry->size;
-       if (!trg_entry->delta) {
-               max_size = trg_size/2 - 20;
+       trg_size = SIZE(trg_entry);
+       if (!DELTA(trg_entry)) {
+               max_size = trg_size/2 - the_hash_algo->rawsz;
                ref_depth = 1;
        } else {
-               max_size = trg_entry->delta_size;
+               max_size = DELTA_SIZE(trg_entry);
                ref_depth = trg->depth;
        }
        max_size = (uint64_t)max_size * (max_depth - src->depth) /
                                                (max_depth - ref_depth + 1);
        if (max_size == 0)
                return 0;
-       src_size = src_entry->size;
+       src_size = SIZE(src_entry);
        sizediff = src_size < trg_size ? trg_size - src_size : 0;
        if (sizediff >= max_size)
                return 0;
        if (trg_size < src_size / 32)
                return 0;
 
+       if (!in_same_island(&trg->entry->idx.oid, &src->entry->idx.oid))
+               return 0;
+
        /* Load data if not already done */
        if (!trg->data) {
                read_lock();
-               trg->data = read_sha1_file(trg_entry->idx.oid.hash, &type,
-                                          &sz);
+               trg->data = read_object_file(&trg_entry->idx.oid, &type, &sz);
                read_unlock();
                if (!trg->data)
-                       die("object %s cannot be read",
+                       die(_("object %s cannot be read"),
                            oid_to_hex(&trg_entry->idx.oid));
                if (sz != trg_size)
-                       die("object %s inconsistent object length (%lu vs %lu)",
+                       die(_("object %s inconsistent object length (%lu vs %lu)"),
                            oid_to_hex(&trg_entry->idx.oid), sz,
                            trg_size);
                *mem_usage += sz;
        }
        if (!src->data) {
                read_lock();
-               src->data = read_sha1_file(src_entry->idx.oid.hash, &type,
-                                          &sz);
+               src->data = read_object_file(&src_entry->idx.oid, &type, &sz);
                read_unlock();
                if (!src->data) {
                        if (src_entry->preferred_base) {
                                static int warned = 0;
                                if (!warned++)
-                                       warning("object %s cannot be read",
+                                       warning(_("object %s cannot be read"),
                                                oid_to_hex(&src_entry->idx.oid));
                                /*
                                 * Those objects are not included in the
@@ -1902,11 +2118,11 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
                                 */
                                return 0;
                        }
-                       die("object %s cannot be read",
+                       die(_("object %s cannot be read"),
                            oid_to_hex(&src_entry->idx.oid));
                }
                if (sz != src_size)
-                       die("object %s inconsistent object length (%lu vs %lu)",
+                       die(_("object %s inconsistent object length (%lu vs %lu)"),
                            oid_to_hex(&src_entry->idx.oid), sz,
                            src_size);
                *mem_usage += sz;
@@ -1916,7 +2132,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
                if (!src->index) {
                        static int warned = 0;
                        if (!warned++)
-                               warning("suboptimal pack - out of memory");
+                               warning(_("suboptimal pack - out of memory"));
                        return 0;
                }
                *mem_usage += sizeof_delta_index(src->index);
@@ -1926,9 +2142,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
        if (!delta_buf)
                return 0;
 
-       if (trg_entry->delta) {
+       if (DELTA(trg_entry)) {
                /* Prefer only shallower same-sized deltas. */
-               if (delta_size == trg_entry->delta_size &&
+               if (delta_size == DELTA_SIZE(trg_entry) &&
                    src->depth + 1 >= trg->depth) {
                        free(delta_buf);
                        return 0;
@@ -1943,7 +2159,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
        free(trg_entry->delta_data);
        cache_lock();
        if (trg_entry->delta_data) {
-               delta_cache_size -= trg_entry->delta_size;
+               delta_cache_size -= DELTA_SIZE(trg_entry);
                trg_entry->delta_data = NULL;
        }
        if (delta_cacheable(src_size, trg_size, delta_size)) {
@@ -1955,8 +2171,8 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
                free(delta_buf);
        }
 
-       trg_entry->delta = src_entry;
-       trg_entry->delta_size = delta_size;
+       SET_DELTA(trg_entry, src_entry);
+       SET_DELTA_SIZE(trg_entry, delta_size);
        trg->depth = src->depth + 1;
 
        return 1;
@@ -1964,13 +2180,13 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
 
 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
 {
-       struct object_entry *child = me->delta_child;
+       struct object_entry *child = DELTA_CHILD(me);
        unsigned int m = n;
        while (child) {
                unsigned int c = check_delta_limit(child, n + 1);
                if (m < c)
                        m = c;
-               child = child->delta_sibling;
+               child = DELTA_SIBLING(child);
        }
        return m;
 }
@@ -1981,7 +2197,7 @@ static unsigned long free_unpacked(struct unpacked *n)
        free_delta_index(n->index);
        n->index = NULL;
        if (n->data) {
-               freed_mem += n->entry->size;
+               freed_mem += SIZE(n->entry);
                FREE_AND_NULL(n->data);
        }
        n->entry = NULL;
@@ -2039,7 +2255,7 @@ static void find_deltas(struct object_entry **list, unsigned *list_size,
                 * otherwise they would become too deep.
                 */
                max_depth = depth;
-               if (entry->delta_child) {
+               if (DELTA_CHILD(entry)) {
                        max_depth -= check_delta_limit(entry, 0);
                        if (max_depth <= 0)
                                goto next;
@@ -2077,19 +2293,26 @@ static void find_deltas(struct object_entry **list, unsigned *list_size,
                 * between writes at that moment.
                 */
                if (entry->delta_data && !pack_to_stdout) {
-                       entry->z_delta_size = do_compress(&entry->delta_data,
-                                                         entry->delta_size);
-                       cache_lock();
-                       delta_cache_size -= entry->delta_size;
-                       delta_cache_size += entry->z_delta_size;
-                       cache_unlock();
+                       unsigned long size;
+
+                       size = do_compress(&entry->delta_data, DELTA_SIZE(entry));
+                       if (size < (1U << OE_Z_DELTA_BITS)) {
+                               entry->z_delta_size = size;
+                               cache_lock();
+                               delta_cache_size -= DELTA_SIZE(entry);
+                               delta_cache_size += entry->z_delta_size;
+                               cache_unlock();
+                       } else {
+                               FREE_AND_NULL(entry->delta_data);
+                               entry->z_delta_size = 0;
+                       }
                }
 
                /* if we made n a delta, and if n is already at max
                 * depth, leaving it in the window is pointless.  we
                 * should evict it first.
                 */
-               if (entry->delta && max_depth <= n->depth)
+               if (DELTA(entry) && max_depth <= n->depth)
                        continue;
 
                /*
@@ -2097,7 +2320,7 @@ static void find_deltas(struct object_entry **list, unsigned *list_size,
                 * currently deltified object, to keep it longer.  It will
                 * be the first base object to be attempted next.
                 */
-               if (entry->delta) {
+               if (DELTA(entry)) {
                        struct unpacked swap = array[best_base];
                        int dist = (window + idx - best_base) % window;
                        int dst = best_base;
@@ -2136,12 +2359,19 @@ static void try_to_free_from_threads(size_t size)
 static try_to_free_t old_try_to_free_routine;
 
 /*
+ * The main object list is split into smaller lists, each is handed to
+ * one worker.
+ *
  * The main thread waits on the condition that (at least) one of the workers
  * has stopped working (which is indicated in the .working member of
  * struct thread_params).
+ *
  * When a work thread has completed its work, it sets .working to 0 and
  * signals the main thread and waits on the condition that .data_ready
  * becomes 1.
+ *
+ * The main thread steals half of the work from the worker that has
+ * most work left to hand it to the idle worker.
  */
 
 struct thread_params {
@@ -2232,8 +2462,8 @@ static void ll_find_deltas(struct object_entry **list, unsigned list_size,
                return;
        }
        if (progress > pack_to_stdout)
-               fprintf(stderr, "Delta compression using up to %d threads.\n",
-                               delta_search_threads);
+               fprintf_ln(stderr, _("Delta compression using up to %d threads"),
+                          delta_search_threads);
        p = xcalloc(delta_search_threads, sizeof(*p));
 
        /* Partition the work amongst work threads. */
@@ -2273,7 +2503,7 @@ static void ll_find_deltas(struct object_entry **list, unsigned list_size,
                ret = pthread_create(&p[i].thread, NULL,
                                     threaded_find_deltas, &p[i]);
                if (ret)
-                       die("unable to create thread: %s", strerror(ret));
+                       die(_("unable to create thread: %s"), strerror(ret));
                active_threads++;
        }
 
@@ -2365,10 +2595,10 @@ static void add_tag_chain(const struct object_id *oid)
        if (packlist_find(&to_pack, oid->hash, NULL))
                return;
 
-       tag = lookup_tag(oid);
+       tag = lookup_tag(the_repository, oid);
        while (1) {
                if (!tag || parse_tag(tag) || !tag->tagged)
-                       die("unable to pack objects reachable from tag %s",
+                       die(_("unable to pack objects reachable from tag %s"),
                            oid_to_hex(oid));
 
                add_object_entry(&tag->object.oid, OBJ_TAG, NULL, 0);
@@ -2397,6 +2627,9 @@ static void prepare_pack(int window, int depth)
        uint32_t i, nr_deltas;
        unsigned n;
 
+       if (use_delta_islands)
+               resolve_tree_islands(the_repository, progress, &to_pack);
+
        get_object_details();
 
        /*
@@ -2418,13 +2651,14 @@ static void prepare_pack(int window, int depth)
        for (i = 0; i < to_pack.nr_objects; i++) {
                struct object_entry *entry = to_pack.objects + i;
 
-               if (entry->delta)
+               if (DELTA(entry))
                        /* This happens if we decided to reuse existing
                         * delta from a pack.  "reuse_delta &&" is implied.
                         */
                        continue;
 
-               if (entry->size < 50)
+               if (!entry->type_valid ||
+                   oe_size_less_than(&to_pack, entry, 50))
                        continue;
 
                if (entry->no_try_delta)
@@ -2432,11 +2666,11 @@ static void prepare_pack(int window, int depth)
 
                if (!entry->preferred_base) {
                        nr_deltas++;
-                       if (entry->type < 0)
-                               die("unable to get type of object %s",
+                       if (oe_type(entry) < 0)
+                               die(_("unable to get type of object %s"),
                                    oid_to_hex(&entry->idx.oid));
                } else {
-                       if (entry->type < 0) {
+                       if (oe_type(entry) < 0) {
                                /*
                                 * This object is not found, but we
                                 * don't have to include it anyway.
@@ -2457,7 +2691,7 @@ static void prepare_pack(int window, int depth)
                ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
                stop_progress(&progress_state);
                if (nr_done != nr_deltas)
-                       die("inconsistency with delta count");
+                       die(_("inconsistency with delta count"));
        }
        free(delta_list);
 }
@@ -2497,11 +2731,11 @@ static int git_pack_config(const char *k, const char *v, void *cb)
        if (!strcmp(k, "pack.threads")) {
                delta_search_threads = git_config_int(k, v);
                if (delta_search_threads < 0)
-                       die("invalid number of threads specified (%d)",
+                       die(_("invalid number of threads specified (%d)"),
                            delta_search_threads);
 #ifdef NO_PTHREADS
                if (delta_search_threads != 1) {
-                       warning("no threads support, ignoring %s", k);
+                       warning(_("no threads support, ignoring %s"), k);
                        delta_search_threads = 0;
                }
 #endif
@@ -2510,7 +2744,7 @@ static int git_pack_config(const char *k, const char *v, void *cb)
        if (!strcmp(k, "pack.indexversion")) {
                pack_idx_opts.version = git_config_int(k, v);
                if (pack_idx_opts.version > 2)
-                       die("bad pack.indexversion=%"PRIu32,
+                       die(_("bad pack.indexversion=%"PRIu32),
                            pack_idx_opts.version);
                return 0;
        }
@@ -2528,7 +2762,7 @@ static void read_object_list_from_stdin(void)
                        if (feof(stdin))
                                break;
                        if (!ferror(stdin))
-                               die("fgets returned NULL, not EOF, not error!");
+                               die("BUG: fgets returned NULL, not EOF, not error!");
                        if (errno != EINTR)
                                die_errno("fgets");
                        clearerr(stdin);
@@ -2536,16 +2770,16 @@ static void read_object_list_from_stdin(void)
                }
                if (line[0] == '-') {
                        if (get_oid_hex(line+1, &oid))
-                               die("expected edge object ID, got garbage:\n %s",
+                               die(_("expected edge object ID, got garbage:\n %s"),
                                    line);
                        add_preferred_base(&oid);
                        continue;
                }
                if (parse_oid_hex(line, &oid, &p))
-                       die("expected object ID, got garbage:\n %s", line);
+                       die(_("expected object ID, got garbage:\n %s"), line);
 
                add_preferred_base_object(p + 1);
-               add_object_entry(&oid, 0, p + 1, 0);
+               add_object_entry(&oid, OBJ_NONE, p + 1, 0);
        }
 }
 
@@ -2559,6 +2793,9 @@ static void show_commit(struct commit *commit, void *data)
 
        if (write_bitmap_index)
                index_commit_for_bitmap(commit);
+
+       if (use_delta_islands)
+               propagate_island_marks(commit);
 }
 
 static void show_object(struct object *obj, const char *name, void *data)
@@ -2566,6 +2803,19 @@ static void show_object(struct object *obj, const char *name, void *data)
        add_preferred_base_object(name);
        add_object_entry(&obj->oid, obj->type, name, 0);
        obj->flags |= OBJECT_ADDED;
+
+       if (use_delta_islands) {
+               const char *p;
+               unsigned depth = 0;
+               struct object_entry *ent;
+
+               for (p = strchr(name, '/'); p; p = strchr(p + 1, '/'))
+                       depth++;
+
+               ent = packlist_find(&to_pack, obj->oid.hash, NULL);
+               if (ent && depth > oe_tree_depth(&to_pack, ent))
+                       oe_set_tree_depth(&to_pack, ent, depth);
+       }
 }
 
 static void show_object__ma_allow_any(struct object *obj, const char *name, void *data)
@@ -2674,14 +2924,14 @@ static void add_objects_in_unpacked_packs(struct rev_info *revs)
 
        memset(&in_pack, 0, sizeof(in_pack));
 
-       for (p = packed_git; p; p = p->next) {
+       for (p = get_all_packs(the_repository); p; p = p->next) {
                struct object_id oid;
                struct object *o;
 
-               if (!p->pack_local || p->pack_keep)
+               if (!p->pack_local || p->pack_keep || p->pack_keep_in_core)
                        continue;
                if (open_pack_index(p))
-                       die("cannot open pack index");
+                       die(_("cannot open pack index"));
 
                ALLOC_GROW(in_pack.array,
                           in_pack.nr + p->num_objects,
@@ -2709,10 +2959,10 @@ static void add_objects_in_unpacked_packs(struct rev_info *revs)
 static int add_loose_object(const struct object_id *oid, const char *path,
                            void *data)
 {
-       enum object_type type = sha1_object_info(oid->hash, NULL);
+       enum object_type type = oid_object_info(the_repository, oid, NULL);
 
        if (type < 0) {
-               warning("loose object at %s could not be examined", path);
+               warning(_("loose object at %s could not be examined"), path);
                return 0;
        }
 
@@ -2737,16 +2987,18 @@ static int has_sha1_pack_kept_or_nonlocal(const struct object_id *oid)
        static struct packed_git *last_found = (void *)1;
        struct packed_git *p;
 
-       p = (last_found != (void *)1) ? last_found : packed_git;
+       p = (last_found != (void *)1) ? last_found :
+                                       get_all_packs(the_repository);
 
        while (p) {
-               if ((!p->pack_local || p->pack_keep) &&
+               if ((!p->pack_local || p->pack_keep ||
+                               p->pack_keep_in_core) &&
                        find_pack_entry_one(oid->hash, p)) {
                        last_found = p;
                        return 1;
                }
                if (p == last_found)
-                       p = packed_git;
+                       p = get_all_packs(the_repository);
                else
                        p = p->next;
                if (p == last_found)
@@ -2782,12 +3034,12 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
        uint32_t i;
        struct object_id oid;
 
-       for (p = packed_git; p; p = p->next) {
-               if (!p->pack_local || p->pack_keep)
+       for (p = get_all_packs(the_repository); p; p = p->next) {
+               if (!p->pack_local || p->pack_keep || p->pack_keep_in_core)
                        continue;
 
                if (open_pack_index(p))
-                       die("cannot open pack index");
+                       die(_("cannot open pack index"));
 
                for (i = 0; i < p->num_objects; i++) {
                        nth_packed_object_oid(&oid, p, i);
@@ -2795,7 +3047,7 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
                            !has_sha1_pack_kept_or_nonlocal(&oid) &&
                            !loosened_object_can_be_discarded(&oid, p->mtime))
                                if (force_object_loose(&oid, p->mtime))
-                                       die("unable to force loose object");
+                                       die(_("unable to force loose object"));
                }
        }
 }
@@ -2809,18 +3061,20 @@ static int pack_options_allow_reuse(void)
 {
        return pack_to_stdout &&
               allow_ofs_delta &&
-              !ignore_packed_keep &&
+              !ignore_packed_keep_on_disk &&
+              !ignore_packed_keep_in_core &&
               (!local || !have_non_local_packs) &&
               !incremental;
 }
 
 static int get_object_list_from_bitmap(struct rev_info *revs)
 {
-       if (prepare_bitmap_walk(revs) < 0)
+       if (!(bitmap_git = prepare_bitmap_walk(revs)))
                return -1;
 
        if (pack_options_allow_reuse() &&
            !reuse_partial_packfile_from_bitmap(
+                       bitmap_git,
                        &reuse_packfile,
                        &reuse_packfile_objects,
                        &reuse_packfile_offset)) {
@@ -2829,7 +3083,7 @@ static int get_object_list_from_bitmap(struct rev_info *revs)
                display_progress(progress_state, nr_result);
        }
 
-       traverse_bitmap_commit_list(&add_object_entry_from_bitmap);
+       traverse_bitmap_commit_list(bitmap_git, &add_object_entry_from_bitmap);
        return 0;
 }
 
@@ -2851,12 +3105,13 @@ static void get_object_list(int ac, const char **av)
        char line[1000];
        int flags = 0;
 
-       init_revisions(&revs, NULL);
+       repo_init_revisions(the_repository, &revs, NULL);
        save_commit_buffer = 0;
+       revs.allow_exclude_promisor_objects_opt = 1;
        setup_revisions(ac, av, &revs, NULL);
 
        /* make sure shallows are read */
-       is_repository_shallow();
+       is_repository_shallow(the_repository);
 
        while (fgets(line, sizeof(line), stdin) != NULL) {
                int len = strlen(line);
@@ -2874,21 +3129,24 @@ static void get_object_list(int ac, const char **av)
                                struct object_id oid;
                                if (get_oid_hex(line + 10, &oid))
                                        die("not an SHA-1 '%s'", line + 10);
-                               register_shallow(&oid);
+                               register_shallow(the_repository, &oid);
                                use_bitmap_index = 0;
                                continue;
                        }
-                       die("not a rev '%s'", line);
+                       die(_("not a rev '%s'"), line);
                }
                if (handle_revision_arg(line, &revs, flags, REVARG_CANNOT_BE_FILENAME))
-                       die("bad revision '%s'", line);
+                       die(_("bad revision '%s'"), line);
        }
 
        if (use_bitmap_index && !get_object_list_from_bitmap(&revs))
                return;
 
+       if (use_delta_islands)
+               load_delta_islands(the_repository);
+
        if (prepare_revision_walk(&revs))
-               die("revision walk setup failed");
+               die(_("revision walk setup failed"));
        mark_edges_uninteresting(&revs, show_edge);
 
        if (!fn_show_object)
@@ -2901,9 +3159,9 @@ static void get_object_list(int ac, const char **av)
                revs.ignore_missing_links = 1;
                if (add_unseen_recent_objects_to_traversal(&revs,
                                unpack_unreachable_expiration))
-                       die("unable to add recent objects");
+                       die(_("unable to add recent objects"));
                if (prepare_revision_walk(&revs))
-                       die("revision walk setup failed");
+                       die(_("revision walk setup failed"));
                traverse_commit_list(&revs, record_recent_commit,
                                     record_recent_object, NULL);
        }
@@ -2918,6 +3176,32 @@ static void get_object_list(int ac, const char **av)
        oid_array_clear(&recent_objects);
 }
 
+static void add_extra_kept_packs(const struct string_list *names)
+{
+       struct packed_git *p;
+
+       if (!names->nr)
+               return;
+
+       for (p = get_all_packs(the_repository); p; p = p->next) {
+               const char *name = basename(p->pack_name);
+               int i;
+
+               if (!p->pack_local)
+                       continue;
+
+               for (i = 0; i < names->nr; i++)
+                       if (!fspathcmp(name, names->items[i].string))
+                               break;
+
+               if (i < names->nr) {
+                       p->pack_keep_in_core = 1;
+                       ignore_packed_keep_in_core = 1;
+                       continue;
+               }
+       }
+}
+
 static int option_parse_index_version(const struct option *opt,
                                      const char *arg, int unset)
 {
@@ -2951,12 +3235,12 @@ static int option_parse_unpack_unreachable(const struct option *opt,
 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 {
        int use_internal_rev_list = 0;
-       int thin = 0;
        int shallow = 0;
        int all_progress_implied = 0;
        struct argv_array rp = ARGV_ARRAY_INIT;
        int rev_list_unpacked = 0, rev_list_all = 0, rev_list_reflog = 0;
        int rev_list_index = 0;
+       struct string_list keep_pack_list = STRING_LIST_INIT_NODUP;
        struct option pack_objects_options[] = {
                OPT_SET_INT('q', "quiet", &progress,
                            N_("do not show progress meter"), 0),
@@ -2967,7 +3251,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                OPT_BOOL(0, "all-progress-implied",
                         &all_progress_implied,
                         N_("similar to --all-progress when progress meter is shown")),
-               { OPTION_CALLBACK, 0, "index-version", NULL, N_("version[,offset]"),
+               { OPTION_CALLBACK, 0, "index-version", NULL, N_("<version>[,<offset>]"),
                  N_("write the pack index file in the specified idx format version"),
                  0, option_parse_index_version },
                OPT_MAGNITUDE(0, "max-pack-size", &pack_size_limit,
@@ -2994,18 +3278,18 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                         N_("do not create an empty pack output")),
                OPT_BOOL(0, "revs", &use_internal_rev_list,
                         N_("read revision arguments from standard input")),
-               { OPTION_SET_INT, 0, "unpacked", &rev_list_unpacked, NULL,
-                 N_("limit the objects to those that are not yet packed"),
-                 PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
-               { OPTION_SET_INT, 0, "all", &rev_list_all, NULL,
-                 N_("include objects reachable from any reference"),
-                 PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
-               { OPTION_SET_INT, 0, "reflog", &rev_list_reflog, NULL,
-                 N_("include objects referred by reflog entries"),
-                 PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
-               { OPTION_SET_INT, 0, "indexed-objects", &rev_list_index, NULL,
-                 N_("include objects referred to by the index"),
-                 PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
+               OPT_SET_INT_F(0, "unpacked", &rev_list_unpacked,
+                             N_("limit the objects to those that are not yet packed"),
+                             1, PARSE_OPT_NONEG),
+               OPT_SET_INT_F(0, "all", &rev_list_all,
+                             N_("include objects reachable from any reference"),
+                             1, PARSE_OPT_NONEG),
+               OPT_SET_INT_F(0, "reflog", &rev_list_reflog,
+                             N_("include objects referred by reflog entries"),
+                             1, PARSE_OPT_NONEG),
+               OPT_SET_INT_F(0, "indexed-objects", &rev_list_index,
+                             N_("include objects referred to by the index"),
+                             1, PARSE_OPT_NONEG),
                OPT_BOOL(0, "stdout", &pack_to_stdout,
                         N_("output pack to stdout")),
                OPT_BOOL(0, "include-tag", &include_tag,
@@ -3021,8 +3305,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                         N_("create thin packs")),
                OPT_BOOL(0, "shallow", &shallow,
                         N_("create packs suitable for shallow fetches")),
-               OPT_BOOL(0, "honor-pack-keep", &ignore_packed_keep,
+               OPT_BOOL(0, "honor-pack-keep", &ignore_packed_keep_on_disk,
                         N_("ignore packs that have companion .keep file")),
+               OPT_STRING_LIST(0, "keep-pack", &keep_pack_list, N_("name"),
+                               N_("ignore this pack")),
                OPT_INTEGER(0, "compression", &pack_compression_level,
                            N_("pack compression level")),
                OPT_SET_INT(0, "keep-true-parents", &grafts_replace_parents,
@@ -3037,10 +3323,15 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                  option_parse_missing_action },
                OPT_BOOL(0, "exclude-promisor-objects", &exclude_promisor_objects,
                         N_("do not pack objects in promisor packfiles")),
+               OPT_BOOL(0, "delta-islands", &use_delta_islands,
+                        N_("respect islands during delta compression")),
                OPT_END(),
        };
 
-       check_replace_refs = 0;
+       if (DFS_NUM_STATES > (1 << OE_DFS_STATE_BITS))
+               BUG("too many dfs states, increase OE_DFS_STATE_BITS");
+
+       read_replace_refs = 0;
 
        reset_pack_idx_option(&pack_idx_opts);
        git_config(git_pack_config, NULL);
@@ -3056,6 +3347,17 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
        if (pack_to_stdout != !base_name || argc)
                usage_with_options(pack_usage, pack_objects_options);
 
+       if (depth >= (1 << OE_DEPTH_BITS)) {
+               warning(_("delta chain depth %d is too deep, forcing %d"),
+                       depth, (1 << OE_DEPTH_BITS) - 1);
+               depth = (1 << OE_DEPTH_BITS) - 1;
+       }
+       if (cache_max_small_delta_size >= (1U << OE_Z_DELTA_BITS)) {
+               warning(_("pack.deltaCacheLimit is too high, forcing %d"),
+                       (1U << OE_Z_DELTA_BITS) - 1);
+               cache_max_small_delta_size = (1U << OE_Z_DELTA_BITS) - 1;
+       }
+
        argv_array_push(&rp, "pack-objects");
        if (thin) {
                use_internal_rev_list = 1;
@@ -3087,41 +3389,43 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                fetch_if_missing = 0;
                argv_array_push(&rp, "--exclude-promisor-objects");
        }
+       if (unpack_unreachable || keep_unreachable || pack_loose_unreachable)
+               use_internal_rev_list = 1;
 
        if (!reuse_object)
                reuse_delta = 0;
        if (pack_compression_level == -1)
                pack_compression_level = Z_DEFAULT_COMPRESSION;
        else if (pack_compression_level < 0 || pack_compression_level > Z_BEST_COMPRESSION)
-               die("bad pack compression level %d", pack_compression_level);
+               die(_("bad pack compression level %d"), pack_compression_level);
 
        if (!delta_search_threads)      /* --threads=0 means autodetect */
                delta_search_threads = online_cpus();
 
 #ifdef NO_PTHREADS
        if (delta_search_threads != 1)
-               warning("no threads support, ignoring --threads");
+               warning(_("no threads support, ignoring --threads"));
 #endif
        if (!pack_to_stdout && !pack_size_limit)
                pack_size_limit = pack_size_limit_cfg;
        if (pack_to_stdout && pack_size_limit)
-               die("--max-pack-size cannot be used to build a pack for transfer.");
+               die(_("--max-pack-size cannot be used to build a pack for transfer"));
        if (pack_size_limit && pack_size_limit < 1024*1024) {
-               warning("minimum pack size limit is 1 MiB");
+               warning(_("minimum pack size limit is 1 MiB"));
                pack_size_limit = 1024*1024;
        }
 
        if (!pack_to_stdout && thin)
-               die("--thin cannot be used to build an indexable pack.");
+               die(_("--thin cannot be used to build an indexable pack"));
 
        if (keep_unreachable && unpack_unreachable)
-               die("--keep-unreachable and --unpack-unreachable are incompatible.");
+               die(_("--keep-unreachable and --unpack-unreachable are incompatible"));
        if (!rev_list_all || !rev_list_reflog || !rev_list_index)
                unpack_unreachable_expiration = 0;
 
        if (filter_options.choice) {
                if (!pack_to_stdout)
-                       die("cannot use --filter without --stdout.");
+                       die(_("cannot use --filter without --stdout"));
                use_bitmap_index = 0;
        }
 
@@ -3141,32 +3445,35 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                use_bitmap_index = use_bitmap_index_default;
 
        /* "hard" reasons not to use bitmaps; these just won't work at all */
-       if (!use_internal_rev_list || (!pack_to_stdout && write_bitmap_index) || is_repository_shallow())
+       if (!use_internal_rev_list || (!pack_to_stdout && write_bitmap_index) || is_repository_shallow(the_repository))
                use_bitmap_index = 0;
 
        if (pack_to_stdout || !rev_list_all)
                write_bitmap_index = 0;
 
+       if (use_delta_islands)
+               argv_array_push(&rp, "--topo-order");
+
        if (progress && all_progress_implied)
                progress = 2;
 
-       prepare_packed_git();
-       if (ignore_packed_keep) {
+       add_extra_kept_packs(&keep_pack_list);
+       if (ignore_packed_keep_on_disk) {
                struct packed_git *p;
-               for (p = packed_git; p; p = p->next)
+               for (p = get_all_packs(the_repository); p; p = p->next)
                        if (p->pack_local && p->pack_keep)
                                break;
                if (!p) /* no keep-able packs found */
-                       ignore_packed_keep = 0;
+                       ignore_packed_keep_on_disk = 0;
        }
        if (local) {
                /*
-                * unlike ignore_packed_keep above, we do not want to
-                * unset "local" based on looking at packs, as it
-                * also covers non-local objects
+                * unlike ignore_packed_keep_on_disk above, we do not
+                * want to unset "local" based on looking at packs, as
+                * it also covers non-local objects
                 */
                struct packed_git *p;
-               for (p = packed_git; p; p = p->next) {
+               for (p = get_all_packs(the_repository); p; p = p->next) {
                        if (!p->pack_local) {
                                have_non_local_packs = 1;
                                break;
@@ -3174,8 +3481,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                }
        }
 
+       prepare_packing_data(&to_pack);
+
        if (progress)
-               progress_state = start_progress(_("Counting objects"), 0);
+               progress_state = start_progress(_("Enumerating objects"), 0);
        if (!use_internal_rev_list)
                read_object_list_from_stdin();
        else {
@@ -3193,8 +3502,9 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                prepare_pack(window, depth);
        write_pack_file();
        if (progress)
-               fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
-                       " reused %"PRIu32" (delta %"PRIu32")\n",
-                       written, written_delta, reused, reused_delta);
+               fprintf_ln(stderr,
+                          _("Total %"PRIu32" (delta %"PRIu32"),"
+                            " reused %"PRIu32" (delta %"PRIu32")"),
+                          written, written_delta, reused, reused_delta);
        return 0;
 }