Merge branch 'rs/sha1-name-readdir-optim'

Optimize "what are the object names already taken in an alternate
object database?" query that is used to derive the length of prefix
an object name is uniquely abbreviated to.

* rs/sha1-name-readdir-optim:
  sha1_file: guard against invalid loose subdirectory numbers
  sha1_file: let for_each_file_in_obj_subdir() handle subdir names
  p4205: add perf test script for pretty log formats
  sha1_name: cache readdir(3) results in find_short_object_filename()
This commit is contained in:
Junio C Hamano 2017-07-05 13:32:56 -07:00
commit 5ab148dda0
7 changed files with 90 additions and 39 deletions

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@ -537,7 +537,7 @@ static int fsck_cruft(const char *basename, const char *path, void *data)
return 0;
}
static int fsck_subdir(int nr, const char *path, void *progress)
static int fsck_subdir(unsigned int nr, const char *path, void *progress)
{
display_progress(progress, nr + 1);
return 0;

View File

@ -10,7 +10,7 @@ static const char * const prune_packed_usage[] = {
static struct progress *progress;
static int prune_subdir(int nr, const char *path, void *data)
static int prune_subdir(unsigned int nr, const char *path, void *data)
{
int *opts = data;
display_progress(progress, nr + 1);

View File

@ -68,7 +68,7 @@ static int prune_cruft(const char *basename, const char *path, void *data)
return 0;
}
static int prune_subdir(int nr, const char *path, void *data)
static int prune_subdir(unsigned int nr, const char *path, void *data)
{
if (!show_only)
rmdir(path);

19
cache.h
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@ -12,6 +12,7 @@
#include "pack-revindex.h"
#include "hash.h"
#include "path.h"
#include "sha1-array.h"
#ifndef platform_SHA_CTX
/*
@ -1540,6 +1541,16 @@ extern struct alternate_object_database {
struct strbuf scratch;
size_t base_len;
/*
* Used to store the results of readdir(3) calls when searching
* for unique abbreviated hashes. This cache is never
* invalidated, thus it's racy and not necessarily accurate.
* That's fine for its purpose; don't use it for tasks requiring
* greater accuracy!
*/
char loose_objects_subdir_seen[256];
struct oid_array loose_objects_cache;
char path[FLEX_ARRAY];
} *alt_odb_list;
extern void prepare_alt_odb(void);
@ -1755,9 +1766,15 @@ typedef int each_loose_object_fn(const struct object_id *oid,
typedef int each_loose_cruft_fn(const char *basename,
const char *path,
void *data);
typedef int each_loose_subdir_fn(int nr,
typedef int each_loose_subdir_fn(unsigned int nr,
const char *path,
void *data);
int for_each_file_in_obj_subdir(unsigned int subdir_nr,
struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data);
int for_each_loose_file_in_objdir(const char *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,

View File

@ -3735,22 +3735,32 @@ void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
typename(expect));
}
static int for_each_file_in_obj_subdir(int subdir_nr,
int for_each_file_in_obj_subdir(unsigned int subdir_nr,
struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data)
{
size_t baselen = path->len;
DIR *dir = opendir(path->buf);
size_t origlen, baselen;
DIR *dir;
struct dirent *de;
int r = 0;
if (subdir_nr > 0xff)
BUG("invalid loose object subdirectory: %x", subdir_nr);
origlen = path->len;
strbuf_complete(path, '/');
strbuf_addf(path, "%02x", subdir_nr);
baselen = path->len;
dir = opendir(path->buf);
if (!dir) {
if (errno == ENOENT)
return 0;
return error_errno("unable to open %s", path->buf);
if (errno != ENOENT)
r = error_errno("unable to open %s", path->buf);
strbuf_setlen(path, origlen);
return r;
}
while ((de = readdir(dir))) {
@ -3788,6 +3798,8 @@ static int for_each_file_in_obj_subdir(int subdir_nr,
if (!r && subdir_cb)
r = subdir_cb(subdir_nr, path->buf, data);
strbuf_setlen(path, origlen);
return r;
}
@ -3797,15 +3809,12 @@ int for_each_loose_file_in_objdir_buf(struct strbuf *path,
each_loose_subdir_fn subdir_cb,
void *data)
{
size_t baselen = path->len;
int r = 0;
int i;
for (i = 0; i < 256; i++) {
strbuf_addf(path, "/%02x", i);
r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
subdir_cb, data);
strbuf_setlen(path, baselen);
if (r)
break;
}

View File

@ -78,10 +78,19 @@ static void update_candidates(struct disambiguate_state *ds, const struct object
/* otherwise, current can be discarded and candidate is still good */
}
static int append_loose_object(const struct object_id *oid, const char *path,
void *data)
{
oid_array_append(data, oid);
return 0;
}
static int match_sha(unsigned, const unsigned char *, const unsigned char *);
static void find_short_object_filename(struct disambiguate_state *ds)
{
int subdir_nr = ds->bin_pfx.hash[0];
struct alternate_object_database *alt;
char hex[GIT_MAX_HEXSZ];
static struct alternate_object_database *fakeent;
if (!fakeent) {
@ -96,29 +105,29 @@ static void find_short_object_filename(struct disambiguate_state *ds)
}
fakeent->next = alt_odb_list;
xsnprintf(hex, sizeof(hex), "%.2s", ds->hex_pfx);
for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
int pos;
if (!alt->loose_objects_subdir_seen[subdir_nr]) {
struct strbuf *buf = alt_scratch_buf(alt);
struct dirent *de;
DIR *dir;
strbuf_addf(buf, "%.2s/", ds->hex_pfx);
dir = opendir(buf->buf);
if (!dir)
continue;
while (!ds->ambiguous && (de = readdir(dir)) != NULL) {
struct object_id oid;
if (strlen(de->d_name) != GIT_SHA1_HEXSZ - 2)
continue;
if (memcmp(de->d_name, ds->hex_pfx + 2, ds->len - 2))
continue;
memcpy(hex + 2, de->d_name, GIT_SHA1_HEXSZ - 2);
if (!get_oid_hex(hex, &oid))
update_candidates(ds, &oid);
for_each_file_in_obj_subdir(subdir_nr, buf,
append_loose_object,
NULL, NULL,
&alt->loose_objects_cache);
alt->loose_objects_subdir_seen[subdir_nr] = 1;
}
pos = oid_array_lookup(&alt->loose_objects_cache, &ds->bin_pfx);
if (pos < 0)
pos = -1 - pos;
while (!ds->ambiguous && pos < alt->loose_objects_cache.nr) {
const struct object_id *oid;
oid = alt->loose_objects_cache.oid + pos;
if (!match_sha(ds->len, ds->bin_pfx.hash, oid->hash))
break;
update_candidates(ds, oid);
pos++;
}
closedir(dir);
}
}

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@ -0,0 +1,16 @@
#!/bin/sh
test_description='Tests the performance of various pretty format placeholders'
. ./perf-lib.sh
test_perf_default_repo
for format in %H %h %T %t %P %p %h-%h-%h
do
test_perf "log with $format" "
git log --format=\"$format\" >/dev/null
"
done
test_done