diff options
| author |  Ben Peart <benpeart@microsoft.com> | 2017-10-18 10:27:25 -0400 |
|---|---|---|
| committer |  Junio C Hamano <gitster@pobox.com> | 2017-11-08 10:39:41 +0900 |
| commit | 00ec50e56d136de41f43c33f39cdbee83f3e4458 (patch) | |
| tree | 31f42fd87d978a2d4d3515d7bfa916e4427eb8c7 | |
| parent | Git 2.14.3 (diff) | |
| download | tgif-00ec50e56d136de41f43c33f39cdbee83f3e4458.tar.xz | |
read_index_from(): speed index loading by skipping verification of the entry order
There is code in post_read_index_from() to catch out of order
entries when reading an index file. This order verification is ~13%
of the cost of every call to read_index_from().
Update check_ce_order() so that it skips this verification unless
the "verify_ce_order" global variable is set.
Teach fsck to force this verification.
The effect can be seen using t/perf/p0002-read-cache.sh:
Test HEAD HEAD~1
--------------------------------------------------------------------------------------
0002.1: read_cache/discard_cache 1000 times 0.41(0.04+0.04) 0.50(0.00+0.10) +22.0%
Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
| -rw-r--r-- | builtin/fsck.c | 1 | ||||
| -rw-r--r-- | cache.h | 1 | ||||
| -rw-r--r-- | read-cache.c | 6 |
3 files changed, 8 insertions, 0 deletions
diff --git a/builtin/fsck.c b/builtin/fsck.c index d18244ab54..81cc5ad78d 100644 --- a/builtin/fsck.c +++ b/builtin/fsck.c @@ -763,6 +763,7 @@ int cmd_fsck(int argc, const char **argv, const char *prefix) if (keep_cache_objects) { verify_index_checksum = 1; + verify_ce_order = 1; read_cache(); for (i = 0; i < active_nr; i++) { unsigned int mode; @@ -720,6 +720,7 @@ extern int hold_locked_index(struct lock_file *, int); extern void set_alternate_index_output(const char *); extern int verify_index_checksum; +extern int verify_ce_order; /* Environment bits from configuration mechanism */ extern int trust_executable_bit; diff --git a/read-cache.c b/read-cache.c index 5e6d24d444..945a377447 100644 --- a/read-cache.c +++ b/read-cache.c @@ -1509,6 +1509,9 @@ struct ondisk_cache_entry_extended { /* Allow fsck to force verification of the index checksum. */ int verify_index_checksum; +/* Allow fsck to force verification of the cache entry order. */ +int verify_ce_order; + static int verify_hdr(struct cache_header *hdr, unsigned long size) { git_SHA_CTX c; @@ -1666,6 +1669,9 @@ static void check_ce_order(struct index_state *istate) { unsigned int i; + if (!verify_ce_order) + return; + for (i = 1; i < istate->cache_nr; i++) { struct cache_entry *ce = istate->cache[i - 1]; struct cache_entry *next_ce = istate->cache[i]; |