[PATCH 11/16] rev-list: add bitmap mode to speed up lists
- From
Vicent Marti <tanoku@gmail.com>
- Date
- Jun 24, 2013, 23:23 UTC
- Message-ID
- <1372116193-32762-12-git-send-email-tanoku@gmail.com>
- In-Reply-To
- <1372116193-32762-1-git-send-email-tanoku@gmail.com>
The bitmap reachability index used to speed up the counting objects phase during `pack-objects` can also be used to optimize a normal rev-list if the only thing required are the SHA1s of the objects during the list.
Calling `git rev-list --use-bitmaps [committish]` is the equivalent of `git rev-list --objects`, but the rev list is performed based on a bitmap result instead of using a manual counting objects phase.
These are some example timings for `torvalds/linux`:
$ time ../git/git rev-list --objects master > /dev/null
real 0m25.567s user 0m25.148s sys 0m0.384s
$ time ../git/git rev-list --use-bitmaps master > /dev/null
real 0m0.393s user 0m0.356s sys 0m0.036s
Additionally, a `--test-bitmap` flag has been added that will perform the same rev-list manually (i.e. using a normal revwalk) and using bitmaps, and verify that the results are the same. --- builtin/rev-list.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/builtin/rev-list.c b/builtin/rev-list.c index 67701be..905ed08 100644 --- a/builtin/rev-list.c +++ b/builtin/rev-list.c @@ -3,6 +3,8 @@ #include "diff.h" #include "revision.h" #include "list-objects.h" +#include "pack.h" +#include "pack-bitmap.h" #include "builtin.h" #include "log-tree.h" #include "graph.h" @@ -256,6 +258,17 @@ static int show_bisect_vars(struct rev_list_info *info, int reaches, int all) return 0; } +static int show_object_fast( + const unsigned char *sha1, + enum object_type type, + uint32_t hash, int exclude, + struct packed_git *found_pack, + off_t found_offset) +{ + fprintf(stdout, "%ss\n", sha1_to_hex(sha1)); + return 1; +} + int cmd_rev_list(int argc, const char **argv, const char *prefix) { struct rev_info revs; @@ -264,6 +277,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) int bisect_list = 0; int bisect_show_vars = 0; int bisect_find_all = 0; + int use_bitmaps = 0; git_config(git_default_config, NULL); init_revisions(&revs, prefix); @@ -305,8 +319,15 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) bisect_show_vars = 1; continue; } + if (!strcmp(arg, "--use-bitmaps")) { + use_bitmaps = 1; + continue; + } + if (!strcmp(arg, "--test-bitmap")) { + test_bitmap_walk(&revs); + return 0; + } usage(rev_list_usage); - } if (revs.commit_format != CMIT_FMT_UNSPECIFIED) { /* The command line has a --pretty */ @@ -332,6 +353,11 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) if (bisect_list) revs.limited = 1; + if (use_bitmaps && !prepare_bitmap_walk(&revs, NULL)) { + traverse_bitmap_commit_list(&show_object_fast); + return 0; + } + if (prepare_revision_walk(&revs)) die("revision walk setup failed"); if (revs.tree_objects)
-- 1.7.9.5