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Re: [Xen-devel] Design document of Kemari

John Levon wrote:
On Sat, Mar 07, 2009 at 01:48:22AM +0900, Yoshiaki Tamura wrote:

I believe Kemari and Remus shares a lot in common.
Stephen and Ian have described both Kemari and Remus on the roadmap document, and that might help for quick review.


In short, Kemari transfers the guest VM on event-driven, while Remus transfers on specific interval.

Thanks. Do you have performance numbers? It sounds like your approach is
intended to give lower I/O response latencies, but Remus will give
better throughput with high I/O load as it doesn't sync on every single
outgoing I/O.

Thanks for your interest.
Although the numbers are old, you can get an extended abstract and slides which I used at Xen Summit from http://www.osrg.net/kemari

The patchset I sent today seems to perform a lot better, but I don't have papers yet.

Regarding the throughput, possible idea is to buffer some events to reduce the frequency, which would introduce latencies as a trade off. Although we haven't implemented this feature yet, it may be interesting how the numbers change.

If both projects are indeed headed for the tree, people are going to
need some ideas of which to use...

Well, I sent the following message when I open-sourced Kemari in November.




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