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From: Pyun YongHyeon <pyunyh@gmail.com>
Date: Fri, 3 Jul 2009 09:47:50 +0900
To: Larry Baird <lab@gta.com>
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Cc: Barney Cordoba <barney_cordoba@yahoo.com>, Paul Thornton <prt@prt.org>,
	freebsd-net@freebsd.org
Subject: Re: Polling and kern.polling.idle_poll
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On Thu, Jul 02, 2009 at 11:31:51AM -0400, Larry Baird wrote:
> > Curious as to why you don't simply lay out the $40 for a modern ethernet card that doesn't need polling to work well?
> These are low end embedded boxs.  No way to upgrade.  But in actuallity
> they have modern (fxp) NICS.  From our testing, live lock is a real issue

Lack of intelligent interrupt mitigation is a weak point of fxp(4)
hardwares. You may not need poling(4) any more on recent PCIe
based fast ethernet controllers.

> for gateways receiving lots of network traffic.  Polling prevents live
> lock.
> 
And it may also add additional latencies.

> Larry