On Thursday 06 May 2004 00:59, Stephen Hemminger wrote:
> > On Wednesday 28 April 2004 00:21, Stephen Hemminger wrote:
> > > This takes the suggestion and makes all the locked skb_ stuff, not
> > > inline. It showed a 3% performance improvement when doing single TCP
> > > stream over 1G Ethernet between SMP machines. Test was average of 10
> > > iterations of iperf for 30 seconds and SUT was 4 way Xeon. Http
> > > performance difference was not noticeable (less than the std. deviation
> > > of the test runs).
>
> The original tests were suspect for a whole lot of reasons. Running the
> proper tests shows no performance differences. The best theory as to why
> there was a difference in earlier tests is that memory debugging was
> enabled; that caused each buffer to be overwritten with a memset. When
> that happened, the test ends up measuring the speed of the memory and cache
> bandwidth, not the CPU or the network.
"no detectable difference" was the most expecter result indeed.
Thank you for actually testing that.
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vda
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