From mboxrd@z Thu Jan  1 00:00:00 1970
From: jamal <hadi@cyberus.ca>
Subject: Re: [PATCH] use mmiowb in tg3_poll
Date: Tue, 31 May 2005 08:53:42 -0400
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To: Arthur Kepner <akepner@sgi.com>
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On Mon, 2005-30-05 at 09:30 -0700, Arthur Kepner wrote:

> I quickly looked through the records that I have and, unfortunately, 
> wasn't able to locate raw data. But I found some scrawlings in my 
> notes which say the most recent measurements for an Altix are: 
> 
> 	i)  PIO read latency ~ 2.4 usec
> 	ii) mmiowb() latency ~ 1.1 usec
> 


In terms of CPU cycles, how many do the above compute to be?
The absolute time numbers you have are also useful for quantification
purposes.

Did i read correctly that your reads are about 2x more expensive than
the writes?

cheers,
jamal