[PATCH 2/3] strbuf.h API users: don't hardcode 8192, use STRBUF_HINT_SIZE
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- Jul 7, 2021, 10:38 UTC
- Message-ID
- <patch-2.3-a920a9971e8-20210707T103712Z-avarab@gmail.com>
- In-Reply-To
- <cover-0.3-00000000000-20210707T103712Z-avarab@gmail.com>
Change a couple of users of strbuf_init() that pass a hint of 8192 to pass STRBUF_HINT_SIZE instead.
Both of these hardcoded occurrences pre-date the use of the strbuf API. See 5242bcbb638 (Use strbuf API in cache-tree.c, 2007-09-06) and af6eb82262e (Use strbuf API in apply, blame, commit-tree and diff, 2007-09-06).
In both cases the exact choice of 8192 is rather arbitrary, e.g. for commit buffers I think 1024 or 2048 would probably be a better default (this commit message is getting this commit close to the former, but I daresay it's already way above the average for git commits).
In any case, if we ever tweak STRBUF_HINT_SIZE we'll probably do so on the basis of some codease-wide performance tests, so replacing the hardcoded value with STRBUF_HINT_SIZE should be safe, they're the same now, and if we change STRBUF_HINT_SIZE in the future this is one of the main codepaths we'll be testing.
Aside: It's unfortunate that we don't take a "hint" of "0" in strbuf_init() to mean "default" and e.g. "-1" to mean the strbuf_slopbuf (a in STRBUF_INIT). I considered adding that, or splitting them up so you'd do strbuf_init(&buf) for the strbuf_init(&buf, 0) case, or strbuf_init_alloc() for the strbuf_init(&buf, N) case, where N > 0. But that would be a big change across the codebase, so let's punt on that for now.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- cache-tree.c | 2 +- commit.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/cache-tree.c b/cache-tree.c index 45e58666afc..d69f6d1c66f 100644 --- a/cache-tree.c +++ b/cache-tree.c @@ -335,7 +335,7 @@ static int update_one(struct cache_tree *it, /* * Then write out the tree object for this level. */ - strbuf_init(&buffer, 8192); + strbuf_init(&buffer, STRBUF_HINT_SIZE); i = 0; while (i < entries) { diff --git a/commit.c b/commit.c index 8ea55a447fa..b3aab46072a 100644 --- a/commit.c +++ b/commit.c @@ -1521,7 +1521,7 @@ int commit_tree_extended(const char *msg, size_t msg_len, /* Not having i18n.commitencoding is the same as having utf-8 */ encoding_is_utf8 = is_encoding_utf8(git_commit_encoding); - strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */ + strbuf_init(&buffer, STRBUF_HINT_SIZE); /* should avoid reallocs for the headers */ strbuf_addf(&buffer, "tree %s\n", oid_to_hex(tree)); /*
-- 2.32.0.636.g43e71d69cff