Re: zero-copy TCP

From: Ingo Molnar (
Date: Mon Sep 04 2000 - 02:54:22 EST

On Mon, 4 Sep 2000 wrote:

> The experiment showed the following prefetching could reduce 20-30% of
> csum_partial_copy_generic() execution time.

Please test it and post the numbers. csum_partial_copy_generic() already
does prefetching - the real test would be to check lat_tcp and bw_tcp
numbers over gigabit, with and without this patch applied. (the same
numbers over localhost dont really count.) Eg. we had smart KNI-based
memcpy routines as well, and it turned out that bw_tcp over gigabit
actually got slower. [testing over 100mbit isnt enough obviously because
x86 CPUs csum much faster than that.]


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

This archive was generated by hypermail 2b29 : Thu Sep 07 2000 - 21:00:17 EST