Nakajima, Jun wrote: > I compared the performance on Xen and KVM for kernel build using the > same guest image. Looks like KVM was (kvm-17) three times slower as far > as we tested, and that high load of qemu was one of the symptoms. We are > looking at the shadow code, but the load of qemu looks very high. I > remember we had similar problems in Xen before, but those were fixed. > Someone should take a look at the qemu side. >
I'd expect the following issues to dominate: - the shadow cache is quite small at 256 pages. Increasing it may increase performance. - we haven't yet taught the scheduler that migrating vcpus is expensive due to the IPI needed to fetch the vmcs. Maybe running with 'taskset 1' would help - shadow eviction policy is FIFO, not LRU, which probably causes many page faults. Running kvm_stat can help show what's going on. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
