From: Alex Riesen Date: Tue, 22 Nov 2005 23:46:22 GMT Subject: Re: [PATCH] speedup allocation in pack-redundant.c Message-ID: <20051122234622.GD2916@steel.home> In-Reply-To: <4383A053.8020100@etek.chalmers.se> Lukas Sandström, Tue, Nov 22, 2005 23:48:51 +0100: > >>Subject: [PATCH] speedup allocation in pack-redundant.c > >>Reuse discarded nodes of llists > >>Signed-off-by: Alex Riesen > > > > I think making allocation/deallocation to the central place is a > > good cleanup, but I am not sure about the free-nodes reusing. > > Does this make difference in real life? If so, it might be > > worth doing the slab-like allocation, since free-nodes are very > > small structure and malloc overhead is not ignorable there. > > > I have done some tests, and unfortunatley I saw approx. zero > improvement with Alex's patch. (less than 10ms difference when > total runtime is 1.850s, tested on http://home.arcor.de/fork0/download/idx.tar.gz) Can I suggest you try it in a really really weird environment? Like Cygwin. And switch some virus scanner on. > Did someone else notice an improvement? My test case had over 100k files in it (just don't ask why. Weird environments, weird projects, ...) > It's a nice idea though. I'll look into doing slab-allocation > for the fun of it, but I'm not really sure that malloc is the > bottleneck. Yes, it usually is not a bottleneck. I think, it just another exception.