Messages in this thread | | | Date | Fri, 26 Nov 2004 07:07:12 -0500 (EST) | From | Justin Piszcz <> | Subject | Re: CONFIG_TULIP_NAPI_HW_MITIGATION latency question. |
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Thanks for the info.
On Thu, 25 Nov 2004, Robert Olsson wrote:
> > > > Justin Piszcz writes: > > "at the cost of a small latency" > > > > How much additional latency is added with this option enabled? > > > > 5ms? 10ms? > > > > -> Use Interrupt Mitigation > > x CONFIG_TULIP_NAPI_HW_MITIGATION: > > x Use HW to reduce RX interrupts. Not strict necessary since NAPI > > reduces RX interrupts but itself. Although this reduces RX interrupts even at > > low levels traffic at the cost of a small latency. > > x > > x If in doubt, say Y. > > Hello! > > It's in usec and the tulip only enables this latency when it's needed it > really tries to keep latency down. > > It has three steeps of input control. > > Low rate: No driver latency. No interrupt delay at all. > Medium rate: Samll driver latency. > High rate: Polling via ->poll > > --ro > - 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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