From: Jonathan Nieder Date: Wed, 25 Sep 2013 06:29:55 +0000 (-0700) Subject: Merge branch 'nd/unpack-entry-optim-in-pack-objects' X-Git-Tag: v1.8.5-rc0~78 X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/87bcf148d7a2dd585bbb6ed18dae83a42b45a67a?ds=inline;hp=-c Merge branch 'nd/unpack-entry-optim-in-pack-objects' * nd/unpack-entry-optim-in-pack-objects: pack-objects: no crc check when the cached version is used --- 87bcf148d7a2dd585bbb6ed18dae83a42b45a67a diff --combined sha1_file.c index f1b649742f,6f5a1e0717..f80bbe4674 --- a/sha1_file.c +++ b/sha1_file.c @@@ -614,7 -614,7 +614,7 @@@ static void scan_windows(struct packed_ } } -static int unuse_one_window(struct packed_git *current, int keep_fd) +static int unuse_one_window(struct packed_git *current) { struct packed_git *p, *lru_p = NULL; struct pack_window *lru_w = NULL, *lru_l = NULL; @@@ -628,8 -628,15 +628,8 @@@ pack_mapped -= lru_w->len; if (lru_l) lru_l->next = lru_w->next; - else { + else lru_p->windows = lru_w->next; - if (!lru_p->windows && lru_p->pack_fd != -1 - && lru_p->pack_fd != keep_fd) { - close(lru_p->pack_fd); - pack_open_fds--; - lru_p->pack_fd = -1; - } - } free(lru_w); pack_open_windows--; return 1; @@@ -637,10 -644,10 +637,10 @@@ return 0; } -void release_pack_memory(size_t need, int fd) +void release_pack_memory(size_t need) { size_t cur = pack_mapped; - while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd)) + while (need >= (cur - pack_mapped) && unuse_one_window(NULL)) ; /* nothing */ } @@@ -651,7 -658,7 +651,7 @@@ void *xmmap(void *start, size_t length if (ret == MAP_FAILED) { if (!length) return NULL; - release_pack_memory(length, fd); + release_pack_memory(length); ret = mmap(start, length, prot, flags, fd, offset); if (ret == MAP_FAILED) die_errno("Out of memory? mmap failed"); @@@ -675,83 -682,6 +675,83 @@@ void close_pack_windows(struct packed_g } } +/* + * The LRU pack is the one with the oldest MRU window, preferring packs + * with no used windows, or the oldest mtime if it has no windows allocated. + */ +static void find_lru_pack(struct packed_git *p, struct packed_git **lru_p, struct pack_window **mru_w, int *accept_windows_inuse) +{ + struct pack_window *w, *this_mru_w; + int has_windows_inuse = 0; + + /* + * Reject this pack if it has windows and the previously selected + * one does not. If this pack does not have windows, reject + * it if the pack file is newer than the previously selected one. + */ + if (*lru_p && !*mru_w && (p->windows || p->mtime > (*lru_p)->mtime)) + return; + + for (w = this_mru_w = p->windows; w; w = w->next) { + /* + * Reject this pack if any of its windows are in use, + * but the previously selected pack did not have any + * inuse windows. Otherwise, record that this pack + * has windows in use. + */ + if (w->inuse_cnt) { + if (*accept_windows_inuse) + has_windows_inuse = 1; + else + return; + } + + if (w->last_used > this_mru_w->last_used) + this_mru_w = w; + + /* + * Reject this pack if it has windows that have been + * used more recently than the previously selected pack. + * If the previously selected pack had windows inuse and + * we have not encountered a window in this pack that is + * inuse, skip this check since we prefer a pack with no + * inuse windows to one that has inuse windows. + */ + if (*mru_w && *accept_windows_inuse == has_windows_inuse && + this_mru_w->last_used > (*mru_w)->last_used) + return; + } + + /* + * Select this pack. + */ + *mru_w = this_mru_w; + *lru_p = p; + *accept_windows_inuse = has_windows_inuse; +} + +static int close_one_pack(void) +{ + struct packed_git *p, *lru_p = NULL; + struct pack_window *mru_w = NULL; + int accept_windows_inuse = 1; + + for (p = packed_git; p; p = p->next) { + if (p->pack_fd == -1) + continue; + find_lru_pack(p, &lru_p, &mru_w, &accept_windows_inuse); + } + + if (lru_p) { + close(lru_p->pack_fd); + pack_open_fds--; + lru_p->pack_fd = -1; + return 1; + } + + return 0; +} + void unuse_pack(struct pack_window **w_cursor) { struct pack_window *w = *w_cursor; @@@ -847,7 -777,7 +847,7 @@@ static int open_packed_git_1(struct pac pack_max_fds = 1; } - while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1)) + while (pack_max_fds <= pack_open_fds && close_one_pack()) ; /* nothing */ p->pack_fd = git_open_noatime(p->pack_name); @@@ -963,7 -893,7 +963,7 @@@ unsigned char *use_pack(struct packed_g win->len = (size_t)len; pack_mapped += win->len; while (packed_git_limit < pack_mapped - && unuse_one_window(p, p->pack_fd)) + && unuse_one_window(p)) ; /* nothing */ win->base = xmmap(NULL, win->len, PROT_READ, MAP_PRIVATE, @@@ -1009,7 -939,7 +1009,7 @@@ static struct packed_git *alloc_packed_ static void try_to_free_pack_memory(size_t size) { - release_pack_memory(size, -1); + release_pack_memory(size); } struct packed_git *add_packed_git(const char *path, int path_len, int local) @@@ -2126,6 -2056,16 +2126,16 @@@ void *unpack_entry(struct packed_git *p int i; struct delta_base_cache_entry *ent; + ent = get_delta_base_cache_entry(p, curpos); + if (eq_delta_base_cache_entry(ent, p, curpos)) { + type = ent->type; + data = ent->data; + size = ent->size; + clear_delta_base_cache_entry(ent); + base_from_cache = 1; + break; + } + if (do_check_packed_object_crc && p->index_version > 1) { struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); unsigned long len = revidx[1].offset - obj_offset; @@@ -2140,16 -2080,6 +2150,6 @@@ } } - ent = get_delta_base_cache_entry(p, curpos); - if (eq_delta_base_cache_entry(ent, p, curpos)) { - type = ent->type; - data = ent->data; - size = ent->size; - clear_delta_base_cache_entry(ent); - base_from_cache = 1; - break; - } - type = unpack_object_header(p, &w_curs, &curpos, &size); if (type != OBJ_OFS_DELTA && type != OBJ_REF_DELTA) break; @@@ -2995,10 -2925,7 +2995,10 @@@ int has_sha1_file(const unsigned char * if (find_pack_entry(sha1, &e)) return 1; - return has_loose_object(sha1); + if (has_loose_object(sha1)) + return 1; + reprepare_packed_git(); + return find_pack_entry(sha1, &e); } static void check_tree(const void *buf, size_t size)