From: Jeff Hostetler Date: Wed, 17 Jan 2018 20:37:55 GMT Subject: Re: [PATCH v2 2/2] sha1_file: improve sha1_file_name() perfs Message-ID: <3cbace45-61df-3074-a48c-66c68c96d542@jeffhostetler.com> In-Reply-To: <20180117175455.9316-2-chriscool@tuxfamily.org> On 1/17/2018 12:54 PM, Christian Couder wrote: > As sha1_file_name() could be performance sensitive, let's > try to make it faster by seeding the initial buffer size > to avoid any need to realloc and by using strbuf_addstr() > and strbuf_addc() instead of strbuf_addf(). > > Helped-by: Derrick Stolee > Helped-by: Jeff Hostetler > Signed-off-by: Christian Couder > --- > sha1_file.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/sha1_file.c b/sha1_file.c > index f66c21b2da..1a94716962 100644 > --- a/sha1_file.c > +++ b/sha1_file.c > @@ -323,8 +323,14 @@ static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1) > > void sha1_file_name(struct strbuf *buf, const unsigned char *sha1) > { > - strbuf_addf(buf, "%s/", get_object_directory()); > + const char *obj_dir = get_object_directory(); > + size_t extra = strlen(obj_dir) + 1 + GIT_MAX_HEXSZ; Very minor nit. Should this be "+3" rather than "+1"? One for the slash after obj_dir, one for the slash between "xx/y[38]", and one for the trailing NUL. > > + if (extra > strbuf_avail(buf)) > + strbuf_grow(buf, extra); > + > + strbuf_addstr(buf, obj_dir); > + strbuf_addch(buf, '/'); > fill_sha1_path(buf, sha1); > } > >