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Date: Sun, 05 Feb 2006 10:11:15 -0800
From: Sam Leffler <sam@errno.com>
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Cc: "freebsd-net@FreeBSD.org" <freebsd-net@freebsd.org>
Subject: Re: Polling for ath driver
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Nate Nielsen wrote:
> I've been working on polling for the FreeBSD ath wireless driver.
> 
> On slow CPU's polling helps prevent (by supressing certain interrupts)
> livelock and increases throughput. This is true of Atheros cards on
> Soekris and other embedded hardware.
> 
> Just thought I'd post something here in case anyone is interested in
> helping with insight, code or testing. I've got a rough (and mostly
> working) patch. There are some locking issues to contend with...

You might try explaining why you think polling helps your performance. 
Unless you've significantly restructured the interrupt handling in the 
driver most work is deferred to a non-interrupt context.  Also the 
driver in 6.0 and later does tx interrupt mitigation and rx interrupt 
coalescing so I wouldn't expect interrupt handling to be a performance 
limitation.  There are other issues that can affect performance but you 
haven't mentioned them...

	Sam