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| author | Elijah Newren <newren@gmail.com> | 2021-07-30 11:47:37 (GMT) |
|---|---|---|
| committer | Junio C Hamano <gitster@pobox.com> | 2021-07-30 16:01:18 (GMT) |
| commit | fa0e936fbb683dbce70b797ae8a5be6b88f48d88 (patch) | |
| tree | edf07ff60d6aa56feedc1992578cd82c03a0c4e4 /diffcore-rename.c | |
| parent | 7afc0b03a2307aa02b7caff2746664e886f38d9a (diff) | |
| download | git-fa0e936fbb683dbce70b797ae8a5be6b88f48d88.zip git-fa0e936fbb683dbce70b797ae8a5be6b88f48d88.tar.gz git-fa0e936fbb683dbce70b797ae8a5be6b88f48d88.tar.bz2 | |
diffcore-rename: use a mem_pool for exact rename detection's hashmap
Exact rename detection, via insert_file_table(), uses a hashmap to store
files by oid. Use a mem_pool for the hashmap entries so these can all be
allocated and deallocated together.
For the testcases mentioned in commit 557ac0350d ("merge-ort: begin
performance work; instrument with trace2_region_* calls", 2020-10-28),
this change improves the performance as follows:
Before After
no-renames: 204.2 ms ± 3.0 ms 202.5 ms ± 3.2 ms
mega-renames: 1.076 s ± 0.015 s 1.072 s ± 0.012 s
just-one-mega: 364.1 ms ± 7.0 ms 357.3 ms ± 3.9 ms
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'diffcore-rename.c')
| -rw-r--r-- | diffcore-rename.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/diffcore-rename.c b/diffcore-rename.c index 4ef0459..73d8840 100644 --- a/diffcore-rename.c +++ b/diffcore-rename.c @@ -317,10 +317,11 @@ static int find_identical_files(struct hashmap *srcs, } static void insert_file_table(struct repository *r, + struct mem_pool *pool, struct hashmap *table, int index, struct diff_filespec *filespec) { - struct file_similarity *entry = xmalloc(sizeof(*entry)); + struct file_similarity *entry = mem_pool_alloc(pool, sizeof(*entry)); entry->index = index; entry->filespec = filespec; @@ -336,7 +337,8 @@ static void insert_file_table(struct repository *r, * and then during the second round we try to match * cache-dirty entries as well. */ -static int find_exact_renames(struct diff_options *options) +static int find_exact_renames(struct diff_options *options, + struct mem_pool *pool) { int i, renames = 0; struct hashmap file_table; @@ -346,7 +348,7 @@ static int find_exact_renames(struct diff_options *options) */ hashmap_init(&file_table, NULL, NULL, rename_src_nr); for (i = rename_src_nr-1; i >= 0; i--) - insert_file_table(options->repo, + insert_file_table(options->repo, pool, &file_table, i, rename_src[i].p->one); @@ -354,8 +356,8 @@ static int find_exact_renames(struct diff_options *options) for (i = 0; i < rename_dst_nr; i++) renames += find_identical_files(&file_table, i, options); - /* Free the hash data structure and entries */ - hashmap_clear_and_free(&file_table, struct file_similarity, entry); + /* Free the hash data structure (entries will be freed with the pool) */ + hashmap_clear(&file_table); return renames; } @@ -1341,6 +1343,7 @@ void diffcore_rename_extended(struct diff_options *options, int num_destinations, dst_cnt; int num_sources, want_copies; struct progress *progress = NULL; + struct mem_pool local_pool; struct dir_rename_info info; struct diff_populate_filespec_options dpf_options = { .check_binary = 0, @@ -1409,11 +1412,18 @@ void diffcore_rename_extended(struct diff_options *options, goto cleanup; /* nothing to do */ trace2_region_enter("diff", "exact renames", options->repo); + mem_pool_init(&local_pool, 32*1024); /* * We really want to cull the candidates list early * with cheap tests in order to avoid doing deltas. */ - rename_count = find_exact_renames(options); + rename_count = find_exact_renames(options, &local_pool); + /* + * Discard local_pool immediately instead of at "cleanup:" in order + * to reduce maximum memory usage; inexact rename detection uses up + * a fair amount of memory, and mem_pools can too. + */ + mem_pool_discard(&local_pool, 0); trace2_region_leave("diff", "exact renames", options->repo); /* Did we only want exact renames? */ |