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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Paul Gortmaker <penguin@muskoka.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Jeff Garzik <jgarzik@pobox.com>
Subject: Re: [PATCH] 2.6.9 Use skb_padto() in drivers/net/8390.c
Date: Mon, 10 Jan 2005 18:28:27 +0000	[thread overview]
Message-ID: <1105381093.12028.81.camel@localhost.localdomain> (raw)
In-Reply-To: <41E1EB68.5000709@muskoka.com>

On Llu, 2005-01-10 at 02:41, Paul Gortmaker wrote:
> Using rdtscl over the  area affected by the patch on the two variants for a
> sample  of 234 small packets, I see an average of 4141 for using the
> existing stack scratch area, and 4162 for using skb_padto.   That is a
> difference of about 0.5%, which is significantly less than the typical
> spread in the samples themselves.  To help give a relevant scale,  feeding
> it a larger 1400 byte packet comes in at around 60,000 cycles on this
> particular box.   Am I being optimistic to see this as good news -- meaning
> that there is no longer a need for driver specific padto implementations,
> whereas it looks like there was back when you did your tests? 

It means that padto has improved a lot (or the underlying allocators).
It also still means the patch makes the code slower and introduces
changes that have no benefit into the kernel, so while its good to see
its not relevant its still a pointless change.


  reply	other threads:[~2005-01-10 20:07 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <41DED9FA.7080106@pobox.com>
2005-01-08  8:33 ` [PATCH] 2.6.9 Use skb_padto() in drivers/net/8390.c] Paul Gortmaker
2005-01-08 15:45   ` Alan Cox
2005-01-10  2:41     ` [PATCH] 2.6.9 Use skb_padto() in drivers/net/8390.c Paul Gortmaker
2005-01-10 18:28       ` Alan Cox [this message]
2005-02-19  5:20         ` Jeff Garzik
2005-02-19 14:06           ` Alan Cox
     [not found] <200501070309.j0739IG6007753@hera.kernel.org>
2005-01-07 15:46 ` Alan Cox

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