From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC PATCH] dynamic_queue_limit.h: Make the struct ___cacheline_aligned_on_smp
Date: Fri, 7 Dec 2012 07:55:59 -0800
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Cc: Tom Herbert <therbert@google.com>,
	David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>
To: Joe Perches <joe@perches.com>
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2012/12/7 Joe Perches <joe@perches.com>:
> Given that the struct will always have limit at the start of
> a cacheline, why not make  struct ___cacheline_aligned_on_smp
> and make limit the first member?
>
> It could make other structs that use struct dql a bit more
> predictable or efficient to pack.
>
> (netdev_queue is size reduced from 256 to 192 on x86-32)
>

No, please.

Have you tested this on a range of hardware and check how it can hurt
performance ?