On Tue, Aug 10, 2010 at 11:55:04PM -0700, Shirley Ma wrote: > On Tue, 2010-08-10 at 23:01 -0700, Shirley Ma wrote: > > On Tue, 2010-08-10 at 18:43 -0700, Shirley Ma wrote: > > > > Also I found some vhost performance regression on the new > > > > kernel with tuning. I used to get 9.4Gb/s, now I couldn't get it. > > > > > > I forgot to mention the kernel I used 2.6.36 one. And I found the > > > native > > > host BW is limited to 8.0Gb/s, so the regression might come from the > > > device driver not vhost. > > > > Something is very interesting, when binding ixgbe interrupts to cpu1, > > and running netperf/netserver on cpu0, the native host to host > > performance is still around 8.0Gb/s, however, the macvtap zero copy > > result is 9.0Gb/s. > > > > root@localhost ~]# netperf -H 192.168.10.74 -c -C -l60 -T0,0 -- -m 64K > > TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.74 (192.168.. > > 10.74) port 0 AF_INET : cpu bind > > 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 65536 60.00 9013.59 53.01 8.21 0.963 0.597 > > > > Below is perf top output: > > > > 578.00 6.5% copy_user_generic_string > > 381.00 4.3% vmx_vcpu_run > > 250.00 2.8% schedule > > 207.00 2.3% vhost_get_vq_desc > > 204.00 2.3% _raw_spin_lock_irqsave > > 197.00 2.2% translate_desc > > 193.00 2.2% memcpy_fromiovec > > 162.00 1.8% gup_pte_range > > > > We can compare your results with mine to see any difference. Could you look at the guest as well? > When binding vhost thread to cpu3, qemu I/O thread to cpu2, macvtap zero > copy patch can get 9.4Gb/s. > > TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.74 (192.168.10.74) port 0 AF_INET : cpu bind > 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 65536 60.00 9408.19 55.69 8.45 0.970 0.589 > > Shirley OTOH CPU utilization is up too. -- MST -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
