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Date: Thu, 7 Apr 2016 23:14:13 +0200
From: Jesper Dangaard Brouer <brouer@redhat.com>
To: Kees Cook <keescook@chromium.org>
Cc: brouer@redhat.com, Thomas Garnier <thgarnie@google.com>,
        Christoph Lameter <cl@linux.com>, Pekka Enberg <penberg@kernel.org>,
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Subject: Re: [RFC v1] mm: SLAB freelist randomization
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On Wed, 6 Apr 2016 14:45:30 -0700 Kees Cook <keescook@chromium.org> wrote:

> On Wed, Apr 6, 2016 at 12:35 PM, Thomas Garnier <thgarnie@google.com> wrote:
[...]
> > re-used on slab creation for performance.  
> 
> I'd like to see some benchmark results for this so the Kconfig can
> include the performance characteristics. I recommend using hackbench
> and kernel build times with a before/after comparison.
> 

It looks like it only happens on init, right? (Thus must bench tools
might not be the right choice).

My slab tools for benchmarking the fastpath is here:
 https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/mm/slab_bulk_test01.c

And I also carry a version of Christoph's slab bench tool:
 https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/mm/slab_test.c

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  Author of http://www.iptv-analyzer.org
  LinkedIn: http://www.linkedin.com/in/brouer