fetch-pack.c: enable fscache for stats under .git/objects

Takuto Ikuta · dscho · commit 8fe910f68f1b · 2018-04-02T22:47:28.000+02:00
When I do git fetch, git call file stats under .git/objects for each
refs. This takes time when there are many refs.

By enabling fscache, git takes file stats by directory traversing and that
improved the speed of fetch-pack for repository having large number of
refs.

In my windows workstation, this improves the time of `git fetch` for
chromium repository like below. I took stats 3 times.

* With this patch
TotalSeconds: 9.9825165
TotalSeconds: 9.1862075
TotalSeconds: 10.1956256
Avg: 9.78811653333333

* Without this patch
TotalSeconds: 15.8406702
TotalSeconds: 15.6248053
TotalSeconds: 15.2085938
Avg: 15.5580231

Signed-off-by: Takuto Ikuta &lt;tikuta@chromium.org&gt;
diff --git a/fetch-pack.c b/fetch-pack.c
@@ -722,6 +722,7 @@ static int everything_local(struct fetch_pack_args *args,
 
 	save_commit_buffer = 0;
 
+	enable_fscache(1);
 	for (ref = *refs; ref; ref = ref->next) {
 		struct object *o;
 
@@ -743,6 +744,7 @@ static int everything_local(struct fetch_pack_args *args,
 				cutoff = commit->date;
 		}
 	}
+	enable_fscache(0);
 
 	if (!args->no_dependents) {
 		if (!args->deepen) {

Original file line number	Diff line number	Diff line change
`@@ -722,6 +722,7 @@ static int everything_local(struct fetch_pack_args *args,`
`722`	`722`
`723`	`723`	`save_commit_buffer = 0;`
`724`	`724`
	`725`	`+ enable_fscache(1);`
`725`	`726`	`for (ref = *refs; ref; ref = ref->next) {`
`726`	`727`	`struct object *o;`
`727`	`728`
`@@ -743,6 +744,7 @@ static int everything_local(struct fetch_pack_args *args,`
`743`	`744`	`cutoff = commit->date;`
`744`	`745`	`}`
`745`	`746`	`}`
	`747`	`+ enable_fscache(0);`
`746`	`748`
`747`	`749`	`if (!args->no_dependents) {`
`748`	`750`	`if (!args->deepen) {`