Re: [PATCH] speedup allocation in pack-redundant.c

From: Lukas Sandström <lukass@etek.chalmers.se>
Date: Nov 22, 2005, 22:48 UTC
Message-ID: <4383A053.8020100@etek.chalmers.se>
In-Reply-To: <7vek58ct4b.fsf@assigned-by-dhcp.cox.net>

Junio C Hamano wrote:

Show 17 quoted lines

> Alex Riesen <raa.lkml@gmail.com> writes:
> 
> 
>>Subject: [PATCH] speedup allocation in pack-redundant.c
>>
>>Reuse discarded nodes of llists
>>
>>Signed-off-by: Alex Riesen <ariesen@harmanbecker.com>
> 
> 
> 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)

Did someone else notice an improvement?

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.

/Lukas