Date: Tue, 20 Dec 2005 10:16:23 -0500 (EST)
From: Steven Rostedt <rostedt@goodmis.org>
To: Ingo Molnar <mingo@elte.hu>
cc: john stultz <johnstul@us.ibm.com>,
       Gunter Ohrner <G.Ohrner@post.rwth-aachen.de>,
       linux-kernel@vger.kernel.org
Subject: Re: 2.6.15-rc5-rt2 slowness
In-Reply-To: <20051220150711.GA5505@elte.hu>
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On Tue, 20 Dec 2005, Ingo Molnar wrote:
>
> * Steven Rostedt <rostedt@goodmis.org> wrote:
>
> > As you see, the new SLOB code runs almost as fast as the SLAB code.
> > With some more improvements, I'm sure it can get even faster.
>
> cool, the numbers are really impressive! I'm wondering where the biggest
> hit comes from - perhaps the SLOB does linear list walking when
> allocating?
>

Yeah, I think that is the biggest hit. The SLOB does the old K&R memory
management. Basically, right from the book.  But it is slow and can
fragment very easily.

I have a little more to do on this patch, (I don't perform the correct
cleanup on kmem_cache_destroy), but I'll send it to you anyway within
the next couple of minutes.  Just so you can take a look and try it out.

-- Steve
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