Re: [RFC][PATCH 12/13] Kemari: use signal to save qemu state for Kemari

[Yoshiaki Tamura <tamura.yoshiaki@lab.ntt.co.jp>]

Christopher Head wrote:
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> Yoshiaki Tamura wrote:
>> Thanks for measuring the numbers.  It made things clear.
>> I think we need a signal-based interface as Ian said previously.
>>
>> On our test environment, AMD Barcelona 2.3GHz, the total cpu cycles of
>> Kemari in userland when running I/O intensive applications is around
>> 3000000.
>> Although Xen transferring code and QEMU saving code is processed
>> concurrently, using xenstored for staring QEMU portion would lower the
>> performance. Especially if the xenstored gets slower when items are
>> loaded.
>>
>> Yoshi
> 
> For Remus, we ended up using a Unix-domain socket to handshake with QEMU
> for suspend/resume, for the same reason (to improve performance compared
> to Xenstore). Just another approach :) and also another approach that
> won't work with stubdom.

Thanks for your info:)
It's good to know that we weren't the only who wanted this kind of interface.

Yoshi