Messages in this thread | | | From | pjd@fred ... | Subject | Re: [patch] ns83820 0.17 | Date | Tue, 12 Mar 2002 14:52:59 -0500 (EST) |
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David Miller wrote: > > I said we don't need NAPI for just bandwidth streams, you mention > routing which is specifically the case I mention that NAPI is good for > (high packet rates).
In particular, if you have a small number of high-speed streams the TCP window mechanism will protect against receive livelock. (actually a medium number of streams would still be protected - it's not until the total offered window size in packets exceeds the input packet queue size that you would become vulnerable to livelock)
Routing, on the other hand, can be driven into a state where you spend all your CPU processing receive interrupts, and no CPU actually forwarding the packets, for a net throughput approaching zero.
Peter Desnoyers - 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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