Messages in this thread | | | Subject | Re: [PATCH] x86: Run checksumming in parallel accross multiple alu's | From | Joe Perches <> | Date | Mon, 14 Oct 2013 15:37:58 -0700 |
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On Mon, 2013-10-14 at 15:18 -0700, Eric Dumazet wrote: > attached patch brings much better results > > lpq83:~# ./netperf -H 7.7.8.84 -l 10 -Cc > MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET > Recv Send Send Utilization Service Demand > Socket Socket Message Elapsed Send Recv Send Recv > Size Size Size Time Throughput local remote local remote > bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB > > 87380 16384 16384 10.00 8043.82 2.32 5.34 0.566 1.304 > > diff --git a/arch/x86/lib/csum-partial_64.c b/arch/x86/lib/csum-partial_64.c [] > @@ -68,7 +68,8 @@ static unsigned do_csum(const unsigned char *buff, unsigned len) > zero = 0; > count64 = count >> 3; > while (count64) { > - asm("addq 0*8(%[src]),%[res]\n\t" > + asm("prefetch 5*64(%[src])\n\t"
Might the prefetch size be too big here?
0x140 is pretty big and is always multiple cachelines no?
> + "addq 0*8(%[src]),%[res]\n\t" > "adcq 1*8(%[src]),%[res]\n\t" > "adcq 2*8(%[src]),%[res]\n\t" > "adcq 3*8(%[src]),%[res]\n\t"
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