Subject: Re: 80Mbps routing with Micrel KS8695
To: Jesse Off <joff@embeddedARM.com>
From: Jason Thorpe <email@example.com>
Date: 01/14/2005 08:04:26
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On Jan 14, 2005, at 7:29 AM, Jesse Off wrote:
> I haven't heard of this "shoot-away" strategy. How much performance is
> gained by not taking Tx interrupts? How do you know when the Tx mbufs
> be freed? It would be interesting to see some "ttcp" or "netperf"
> benchmarks so I could compare against the ep93xx enet driver/hardware.
> Here are some of the ep93xx numbers:
You can gain a lot of performance by not using Tx interrupts, on
devices that can do it.
Basically, lazily/opportunistically GC the Tx descriptors e.g. once per
second, when you get Rx interrupts, and when you run out of descriptors
on the (*if_start)() routine. Look at status bits in the pending
-- Jason R. Thorpe <firstname.lastname@example.org>
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