simple euristic for further free packing improvements

diff --git a/fetch-clone.c b/fetch-clone.c
index 859f4009419d37c2a21ecf6941aaad4fe004e747..da1b3ffbaa13ee4dfc8d080759b3f936850b7647 100644 (file)
--- a/fetch-clone.c
+++ b/fetch-clone.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "exec_cmd.h"
 #include <sys/wait.h>
+#include <sys/time.h>
 
 static int finish_pack(const char *pack_tmp_name, const char *me)
 {
@@ -129,10 +130,35 @@ int receive_unpack_pack(int fd[2], const char *me, int quiet)
        die("git-unpack-objects died of unnatural causes %d", status);
 }
 
-int receive_keep_pack(int fd[2], const char *me)
+/*
+ * We average out the download speed over this many "events", where
+ * an event is a minimum of about half a second. That way, we get
+ * a reasonably stable number.
+ */
+#define NR_AVERAGE (4)
+
+/*
+ * A "binary msec" is a power-of-two-msec, aka 1/1024th of a second.
+ * Keeing the time in that format means that "bytes / msecs" means
+ * is the same as kB/s (modulo rounding).
+ *
+ * 1000512 is a magic number (usecs in a second, rounded up by half
+ * of 1024, to make "rounding" come out right ;)
+ */
+#define usec_to_binarymsec(x) ((int)(x) / (1000512 >> 10))
+
+int receive_keep_pack(int fd[2], const char *me, int quiet)
 {
        char tmpfile[PATH_MAX];
        int ofd, ifd;
+       unsigned long total;
+       static struct timeval prev_tv;
+       struct average {
+               unsigned long bytes;
+               unsigned long time;
+       } download[NR_AVERAGE] = { {0, 0}, };
+       unsigned long avg_bytes, avg_time;
+       int idx = 0;
 
        ifd = fd[0];
        snprintf(tmpfile, sizeof(tmpfile),
@@ -141,6 +167,10 @@ int receive_keep_pack(int fd[2], const char *me)
        if (ofd < 0)
                return error("unable to create temporary file %s", tmpfile);
 
+       gettimeofday(&prev_tv, NULL);
+       total = 0;
+       avg_bytes = 0;
+       avg_time = 0;
        while (1) {
                char buf[8192];
                ssize_t sz, wsz, pos;
@@ -148,10 +178,13 @@ int receive_keep_pack(int fd[2], const char *me)
                if (sz == 0)
                        break;
                if (sz < 0) {
-                       error("error reading pack (%s)", strerror(errno));
-                       close(ofd);
-                       unlink(tmpfile);
-                       return -1;
+                       if (errno != EINTR && errno != EAGAIN) {
+                               error("error reading pack (%s)", strerror(errno));
+                               close(ofd);
+                               unlink(tmpfile);
+                               return -1;
+                       }
+                       sz = 0;
                }
                pos = 0;
                while (pos < sz) {
@@ -165,6 +198,40 @@ int receive_keep_pack(int fd[2], const char *me)
                        }
                        pos += wsz;
                }
+               total += sz;
+               if (!quiet) {
+                       static unsigned long last;
+                       struct timeval tv;
+                       unsigned long diff = total - last;
+                       /* not really "msecs", but a power-of-two millisec (1/1024th of a sec) */
+                       unsigned long msecs;
+
+                       gettimeofday(&tv, NULL);
+                       msecs = tv.tv_sec - prev_tv.tv_sec;
+                       msecs <<= 10;
+                       msecs += usec_to_binarymsec(tv.tv_usec - prev_tv.tv_usec);
+
+                       if (msecs > 500) {
+                               prev_tv = tv;
+                               last = total;
+
+                               /* Update averages ..*/
+                               avg_bytes += diff;
+                               avg_time += msecs;
+                               avg_bytes -= download[idx].bytes;
+                               avg_time -= download[idx].time;
+                               download[idx].bytes = diff;
+                               download[idx].time = msecs;
+                               idx++;
+                               if (idx >= NR_AVERAGE)
+                                       idx = 0;
+
+                               fprintf(stderr, "%4lu.%03luMB  (%lu kB/s)      \r",
+                                       total >> 20,
+                                       1000*((total >> 10) & 1023)>>10,
+                                       avg_bytes / avg_time );
+                       }
+               }
        }
        close(ofd);
        return finish_pack(tmpfile, me);