On Fri, Sep 19, 2008 at 06:30:50PM -0700, Avi Kivity wrote: > Joerg Roedel wrote: > >Ok, here are some performance numbers for nested svm. I ran kernbench -M > >on a virtual machine with 4G RAM and 1 VCPU (since nesting SMP guests > >do currently not work). I measured simple virtualization with a shadow > >paging guest on bare metal and within a nested guest (same guest image) > >on a nested paging enabled first level guest. > > > > | Shadow Guest (100%) | Nested Guest (X) | X > >-----------------+---------------------+-------------------+-------- > >Elapsed Time | 553.244 (1.21208) | 1185.95 (20.0365) | 214.363% > >User Time | 407.728 (0.987279) | 520.434 (8.55643) | 127.642% > >System Time | 144.828 (0.480645) | 664.528 (11.6648) | 458.839% > >Percent CPU | 99 (0) | 99 (0) | 100.000% > >Context Switches | 98265.2 (183.001) | 220015 (3302.74) | 223.899% > >Sleeps | 49397.8 (31.0274) | 49460.2 (364.84) | 100.126% > > > >So we have an overall slowdown in the first nesting level of more than > >50%. Mostly because we spend so much time in the system level. Seems > >there is some work to do for performance improvements :-) > > > > > > Do you have kvm_stat output for the two cases? Also interesting to run > kvm_stat on both guest and host.
Sorry, no. But I can repeat the measurements and gather these numbers. Joerg -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
