From 7c24c3e6ce8faa5a6d23ef9d11c71a0a106b3bb3 Mon Sep 17 00:00:00 2001 From: "W. Felix Handte" Date: Wed, 18 Aug 2021 16:02:01 -0400 Subject: [PATCH] Give Up on Searching End of Block Amusingly, it seems to be a non-trivial performance hit to add in final searches or even hash table insertions during cleanup. So let's not. It seems to not make any meaningful difference in compression ratio. --- lib/compress/zstd_fast.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/lib/compress/zstd_fast.c b/lib/compress/zstd_fast.c index f7df66681..50bceef74 100644 --- a/lib/compress/zstd_fast.c +++ b/lib/compress/zstd_fast.c @@ -354,10 +354,9 @@ _start: /* Requires: ip0 */ } while (ip2 < ilimit); _cleanup: - - /* Find matches at end of block. */ - - /* TODO */ + /* Note that there are probably still a couple positions we could search. + * However, it seems to be a meaningful performance hit to try to search + * them. So let's not. */ /* save reps for next block */ rep[0] = rep_offset1 ? rep_offset1 : offsetSaved;