From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [RFC PATCH] dynamic_queue_limit.h: Make the struct
 ___cacheline_aligned_on_smp
Date: Fri, 07 Dec 2012 08:29:21 -0800
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Cc: Tom Herbert <therbert@google.com>,
	David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 2012-12-07 at 08:19 -0800, Eric Dumazet wrote:
> On Fri, 2012-12-07 at 08:05 -0800, Joe Perches wrote:
> 
> > So it seemed somewhat sensible to make the
> > entire struct in a single cacheline.
> 
> Any layout change in an object used in network fast path need a complete
> performance study.
> 
> Even if you provide such a study, we'll need to reproduce your numbers
> here.
> 
> BQL/DQL is not on our radars, spending two cache lines on a critical
> object is fine.

Well Maybe Tom can provide some information as to why
the limit variable was cacheline_aligned_in_smp and not
the struct.

I didn't find any discussion about it.