From: Sean <seanlkml@sympatico.ca>
Date: Tue, 11 Dec 2007 06:01:30 GMT
Subject: Re: Something is broken in repack
Message-ID: <BAYC1-PASMTP08CFB6F824B1282649E5EAAE640@CEZ.ICE>
In-Reply-To: <9e4733910712102125w56c70c0cxb8b00a060b62077@mail.gmail.com>

On Tue, 11 Dec 2007 00:25:55 -0500
"Jon Smirl" <jonsmirl@gmail.com> wrote:

> Something is hurting bad with threads. 170 CPU minutes with one
> thread, versus 195 CPU minutes with four threads.
> 
> Is there a different memory allocator that can be used when
> multithreaded on gcc? This whole problem may be coming from the memory
> allocation function. git is hardly interacting at all on the thread
> level so it's likely a problem in the C run-time.

You might want to try Google's malloc, it's basically a drop in replacement
with some optional built-in performance monitoring capabilities.  It is said
to be much faster and better at threading than glibc's:

  http://code.google.com/p/google-perftools/wiki/GooglePerformanceTools
  http://google-perftools.googlecode.com/svn/trunk/doc/tcmalloc.html


You can LD_PRELOAD it or link directly.

Cheers,
Sean