Jan Kiszka wrote: > Avi Kivity wrote: > >> Xiaodong Yi wrote: >> >>> Hi, >>> >>> I've tested the guest Linux using UnixBench 5.1.2. The platform is: >>> * Intel's Core Due CPU with 2 cores, 2GB RAM >>> * CentOS 5.2 as the dom0 Linux, i.e., the host Linux for KVM >>> * CentOS 5.2 as the guest Linux, i.e., the Linux running on the >>> virtual machine provided by Qemu >>> >>> The first set of results is for Luvalley, and the second one is for >>> KVM. As the result, Luvalley's guest Linux is 20% ~ 30% faster than >>> KVM's guest! It is very surprise to me. I had through Luvalley's guest >>> should be the same performance as KVM's. >>> >>> >>> >> Yes, it is surprising. >> >> >>> Double-Precision Whetstone 12287.7 MWIPS (10.0 s, 2 samples) >>> Double-Precision Whetstone 2166.3 MWIPS (10.2 s, 2 samples >>> >> That's by far the biggest difference. Can you confirm it isn't a typo? >> >> If not, then it looks like we have a bug in floating point handling. I >> don't think this benchmark uses sse. >> >> > > Even the native Linux numbers are not that high, rather comparable to > KVM. I suspect Luvalley is fooling the benchmark here... > Most likely timing. Likely Luvally guests time runs to slowly, so they achieve more loops per unit of guest time. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. -- 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
