@matheusbsbs / matheus-bagliano / commits / ca54d9baa4

trace: measure where the time is spent in the index-heavy operations

All the known heavy code blocks are measured (except object database access). This should help identify if an optimization is effective or not. An unoptimized git-status would give something like below: 0.001791141 s: read cache ... 0.004011363 s: preload index 0.000516161 s: refresh index 0.003139257 s: git command: ... 'status' '--porcelain=2' 0.006788129 s: diff-files 0.002090267 s: diff-index 0.001885735 s: initialize name hash 0.032013138 s: read directory 0.051781209 s: git command: './git' 'status' Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Nguyễn Thái Ngọc Duy committed Jan 27, 2018 at 19:27 UTC ca54d9baa4a8e73141d4c963245ee6f09dcc994d

5 files changed +18

diff-lib.c

@@ -92,6 +92,7 @@ int run_diff_files(struct rev_info *revs, unsigned int option)

92 int diff_unmerged_stage = revs->max_count;

93 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)

94 ? CE_MATCH_RACY_IS_DIRTY : 0);

95 + uint64_t start = getnanotime();

97 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");

@@ -246,6 +247,7 @@ int run_diff_files(struct rev_info *revs, unsigned int option)

247 }

248 diffcore_std(&revs->diffopt);

249 diff_flush(&revs->diffopt);

250 + trace_performance_since(start, "diff-files");

251 return 0;

252 }

253

@@ -512,6 +514,7 @@ static int diff_cache(struct rev_info *revs,

514 int run_diff_index(struct rev_info *revs, int cached)

515 {

516 struct object_array_entry *ent;

517 + uint64_t start = getnanotime();

518

519 ent = revs->pending.objects;

520 if (diff_cache(revs, &ent->item->oid, ent->name, cached))

@@ -521,6 +524,7 @@ int run_diff_index(struct rev_info *revs, int cached)

524 diffcore_fix_diff_index(&revs->diffopt);

525 diffcore_std(&revs->diffopt);

526 diff_flush(&revs->diffopt);

527 + trace_performance_since(start, "diff-index");

528 return 0;

529 }

530

dir.c

@@ -2248,6 +2248,7 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,

2248 const char *path, int len, const struct pathspec *pathspec)

2249 {

2250 struct untracked_cache_dir *untracked;

2251 + uint64_t start = getnanotime();

2252

2253 if (has_symlink_leading_path(path, len))

2254 return dir->nr;

@@ -2286,6 +2287,7 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,

2287 dir->nr = i;

2288 }

2289

2290 + trace_performance_since(start, "read directory %.*s", len, path);

2291 if (dir->untracked) {

2292 static struct trace_key trace_untracked_stats = TRACE_KEY_INIT(UNTRACKED_STATS);

2293 trace_printf_key(&trace_untracked_stats,

name-hash.c

@@ -578,6 +578,8 @@ static void threaded_lazy_init_name_hash(

578

579 static void lazy_init_name_hash(struct index_state *istate)

580 {

581 + uint64_t start = getnanotime();

582 +

583 if (istate->name_hash_initialized)

584 return;

585 hashmap_init(&istate->name_hash, cache_entry_cmp, NULL, istate->cache_nr);

@@ -600,6 +602,7 @@ static void lazy_init_name_hash(struct index_state *istate)

602 }

603

604 istate->name_hash_initialized = 1;

605 + trace_performance_since(start, "initialize name hash");

606 }

607

608 /*

preload-index.c

@@ -78,6 +78,7 @@ static void preload_index(struct index_state *index,

78 {

79 int threads, i, work, offset;

80 struct thread_data data[MAX_PARALLEL];

81 + uint64_t start = getnanotime();

83 if (!core_preload_index)

84 return;

@@ -108,6 +109,7 @@ static void preload_index(struct index_state *index,

109 if (pthread_join(p->pthread, NULL))

110 die("unable to join threaded lstat");

111 }

112 + trace_performance_since(start, "preload index");

113 }

114 #endif

115

read-cache.c

@@ -1372,6 +1372,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,

1372 const char *typechange_fmt;

1373 const char *added_fmt;

1374 const char *unmerged_fmt;

1375 + uint64_t start = getnanotime();

1376

1377 modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");

1378 deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n");

@@ -1442,6 +1443,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,

1443

1444 replace_index_entry(istate, i, new);

1445 }

1446 + trace_performance_since(start, "refresh index");

1447 return has_errors;

1448 }

1449

@@ -1873,6 +1875,7 @@ static void freshen_shared_index(char *base_sha1_hex, int warn)

1875

1876 int read_index_from(struct index_state *istate, const char *path)

1877 {

1878 + uint64_t start = getnanotime();

1879 struct split_index *split_index;

1880 int ret;

1881 char *base_sha1_hex;

@@ -1883,6 +1886,7 @@ int read_index_from(struct index_state *istate, const char *path)

1886 return istate->cache_nr;

1887

1888 ret = do_read_index(istate, path, 0);

1889 + trace_performance_since(start, "read cache %s", path);

1890

1891 split_index = istate->split_index;

1892 if (!split_index || is_null_sha1(split_index->base_sha1)) {

@@ -1906,6 +1910,7 @@ int read_index_from(struct index_state *istate, const char *path)

1910 freshen_shared_index(base_sha1_hex, 0);

1911 merge_base_index(istate);

1912 post_read_index_from(istate);

1913 + trace_performance_since(start, "read cache %s", base_path);

1914 return ret;

1915 }

1916

@@ -2234,6 +2239,7 @@ void update_index_if_able(struct index_state *istate, struct lock_file *lockfile

2239 static int do_write_index(struct index_state *istate, struct tempfile *tempfile,

2240 int strip_extensions)

2241 {

2242 + uint64_t start = getnanotime();

2243 int newfd = tempfile->fd;

2244 git_SHA_CTX c;

2245 struct cache_header hdr;

@@ -2374,6 +2380,7 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,

2380 return -1;

2381 istate->timestamp.sec = (unsigned int)st.st_mtime;

2382 istate->timestamp.nsec = ST_MTIME_NSEC(st);

2383 + trace_performance_since(start, "write index, changed mask = %x", istate->cache_changed);

2384 return 0;

2385 }

2386