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Native Linux KVM tool v2

Native Linux KVM tool v2

Posted Jun 16, 2011 6:30 UTC (Thu) by penberg (subscriber, #30234)
In reply to: Native Linux KVM tool v2 by stefanha
Parent article: Native Linux KVM tool v2

We tested kvm-qemu.git master. It turns out there are some command line options that will make Qemu perform better but we've yet to test them.

It's never going to be an apples to apples comparison but it goes to show how important _sane default values_ are. I'm willing to bet most people don't know about all the Qemu magic that makes things run faster (which is especially important for virtualized I/O).

And just to set the record straight: the only reason we did the comparison was to see how *badly* we'd compare against Qemu. Turns out we didn't do badly at all so there was no point in hiding our results - even if we have to eat our hats later on!

Disclaimer: I contribute to the tools/kvm project.


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Native Linux KVM tool v2

Posted Jun 17, 2011 13:53 UTC (Fri) by aliguori (subscriber, #30636) [Link]

From Pekka:

It turns out we were benchmarking the wrong guest kernel version for
qemu-kvm which is why it performed so much worse. Here's a summary of
qemu-kvm beating tools/kvm:

https://raw.github.com/gist/1029359/9f9a714ecee64802c08a3455971e410d5029370b/gistfile1.txt

I'd ask for a brown paper bag if I wasn't so busy eating my hat at the moment.

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