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Subject: Re: Please revert [PATCH] user of the jiffies rounding patch: Slab
From: Arjan van de Ven <arjan@linux.intel.com>
To: Christoph Lameter <clameter@sgi.com>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org
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Date: Sat, 28 Apr 2007 16:40:30 -0700
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On Sat, 2007-04-28 at 16:35 -0700, Christoph Lameter wrote:

> Hmmm... Yes but that looks like it comes from a different function. Slab
> calls
> 
>  __round_jiffies_relative(HZ, cpu))
> 
> And its description says:
> 
> /**
>  *
>  * The exact rounding is skewed for each processor to avoid all
>  * processors firing at the exact same time, which could lead
>  * to lock contention or spurious cache line bouncing.


> This is exactly the wrong thing to do.


is it?