From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Kok, Auke" <auke-jan.h.kok@intel.com>
Subject: Re: tbench regression on each kernel release from  2.6.22 -> 2.6.28
Date: Mon, 11 Aug 2008 11:50:57 -0700
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To: Christoph Lameter <cl@linux-foundation.org>
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Christoph Lameter wrote:
> It seems that the network stack becomes slower over time? Here is a list of
> tbench results with various kernel versions:
> 
> 2.6.22		3207.77 mb/sec
> 2.6.24		3185.66
> 2.6.25		2848.83
> 2.6.26		2706.09
> 2.6.27(rc2)	2571.03
> 
> And linux-next is:
> 
> 2.6.28(l-next)	2568.74
> 
> It shows that there is still have work to be done on linux-next. Too close to
> upstream in performance.
> 
> Note the KT event between 2.6.24 and 2.6.25. Why is that?

is this with SLAB or with SLUB? SLUB has been known to impact network performance...

Auke