Messages in this thread | | | Date | Tue, 17 Sep 2002 14:49:11 -0700 (PDT) | Subject | Re: Info: NAPI performance at "low" loads | From | "David S. Miller" <> |
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From: Jeff Garzik <jgarzik@mandrakesoft.com> Date: Tue, 17 Sep 2002 17:54:42 -0400
David S. Miller wrote: > Any driver should be able to get the NAPI overhead to max out at > 2 PIOs per packet. Just to pick nits... my example went from 2 or 3 IOs [depending on the presence/absence of a work loop] to 6 IOs. I mean "2 extra PIOs" not "2 total PIOs".
I think it's doable for just about every driver, even tg3 with it's weird semaphore scheme takes 2 extra PIOs worst case with NAPI.
The semaphore I have to ACK anyways at hw IRQ time anyways, and since I keep a software copy of the IRQ masking register, mask and unmask are each one PIO. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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