On Mon, Nov 20, 2017 at 09:20:35AM -0500, Jeff King wrote: > Out of curiosity, have you tried experimenting with any high-performance > 3rd-party allocator libraries? I've often wondered if we could get a > performance improvement from dropping in a new allocator, but was never > able to measure any real benefit over glibc's ptmalloc2. The situation > might be different on Windows, though (i.e., if the libc allocator isn't > that great). Just linking with tcmalloc, like: diff --git a/Makefile b/Makefile index ee9d5eb11e..4f299cd914 100644 --- a/Makefile +++ b/Makefile @@ -1018,7 +1018,7 @@ BUILTIN_OBJS += builtin/worktree.o BUILTIN_OBJS += builtin/write-tree.o GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB) -EXTLIBS = +EXTLIBS = -ltcmalloc GIT_USER_AGENT = git/$(GIT_VERSION) seems to consistently show about 30% speedup on p0002: Test HEAD^ HEAD -------------------------------------------------------------------------------------- 0002.1: read_cache/discard_cache 1000 times 0.19(0.18+0.01) 0.13(0.12+0.01) -31.6% I don't think we really even need a patch for it. You should be able to just build with: make EXT_LIBS=-ltcmalloc I can't think of any real advantage to a Makefile knob except discoverability. -Peff
