From da470981defcace6e909b74ebc4ab5a40a702728 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Mon, 18 Jul 2016 15:21:38 -0700 Subject: [PATCH] fetch-pack: grow stateless RPC windows exponentially When updating large repositories, the LARGE_FLUSH limit (that is, the limit at which the window growth strategy switches from exponential to linear) is reached quite quickly. Use a conservative exponential growth strategy when that limit is reached instead (and increase LARGE_FLUSH so that there is no regression in window size). This optimization is only applied during stateless RPCs to avoid the issue raised and fixed in commit 44d8dc54 (Fix potential local deadlock during fetch-pack, 2011-03-29). Signed-off-by: Jonathan Tan Reviewed-by: Jonathan Nieder Signed-off-by: Junio C Hamano --- fetch-pack.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/fetch-pack.c b/fetch-pack.c index b501d5c320..85e77af61d 100644 --- a/fetch-pack.c +++ b/fetch-pack.c @@ -243,16 +243,21 @@ static void insert_one_alternate_ref(const struct ref *ref, void *unused) #define INITIAL_FLUSH 16 #define PIPESAFE_FLUSH 32 -#define LARGE_FLUSH 1024 +#define LARGE_FLUSH 16384 static int next_flush(struct fetch_pack_args *args, int count) { - int flush_limit = args->stateless_rpc ? LARGE_FLUSH : PIPESAFE_FLUSH; - - if (count < flush_limit) - count <<= 1; - else - count += flush_limit; + if (args->stateless_rpc) { + if (count < LARGE_FLUSH) + count <<= 1; + else + count = count * 11 / 10; + } else { + if (count < PIPESAFE_FLUSH) + count <<= 1; + else + count += PIPESAFE_FLUSH; + } return count; }