Re: [RFC][PATCH] Check write to slab memory which freed already using mudflap

From: David Rientjes <rientjes@google.com>
To: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Nick Piggin <npiggin@suse.de>, Ingo Molnar <mingo@elte.hu>,
	Janboe Ye <yuan-bo.ye@motorola.com>,
	linux-kernel@vger.kernel.org, vegard.nossum@gmail.com,
	fche@redhat.com, cl@linux-foundation.org
Subject: Re: [RFC][PATCH] Check write to slab memory which freed already using mudflap
Date: Fri, 10 Jul 2009 03:03:19 -0700 (PDT)	[thread overview]
Message-ID: <alpine.DEB.2.00.0907100253560.14601@chino.kir.corp.google.com> (raw)
In-Reply-To: <1247219506.771.22.camel@penberg-laptop>

On Fri, 10 Jul 2009, Pekka Enberg wrote:

> Hey, I said SLAB is on its way out (yes, it really is). But I didn't say
> we're going to blindly remove it if performs better than the
> alternatives. I don't see any reason why SQLB can't reach the same
> performance as SLAB after on fundamental level, though. Can you?
> 

I'm not really interested in making predictions on which design has the 
greatest potential for pure performance, I'm interested in what is proven 
to work and does the job better than any alternative.  Right now, for 
certain workloads, that's undeniably slab.  So I'd disagree that slab is 
on its way out until another allocator is shown to at least have parity 
with it (at which time I'd become more interested in the cleanliness of 
the code, the debugging support, etc.).

It's my opinion that slab is on its way out when there's no benchmark that 
shows it is superior by any significant amount.  If that happens (and if 
its successor is slub, slqb, or a yet to be implemented allocator), we can 
probably start a discussion on what's in and what's out at that time.