From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dario Faggioli <dario.faggioli@citrix.com>
Subject: Re: Can Xen sleep or wake up a thread?
Date: Tue, 8 Oct 2013 18:38:49 +0200
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To: Xinxin Jin <xinxinjin89@gmail.com>
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On mar, 2013-10-08 at 08:11 -0700, Xinxin Jin wrote:
> Hi everyone,
>=20
>=20
> I found in Xen, when synchronization between multiple threads is
> needed, Xen always uses busy wait or simple spin lock.
>
Mmm... What exactly is a 'thread' here? Are you talking about Xen
internals? If yes, I don't think there's much multithreading involved
there...

> In linux, the kernel can block a waiting thread and schedule other
> threads for execution. Why does Xen do not have this mechanism?=20
>
Well, Linux, as a general purpose kernel, does indeed schedule a lot of
different stuff, yes, but I still don't see where you think Xen
could/should do something similar...

> I guess it is because the performance issue? A lot of appreciation for
> your answer !!
>=20
Perhaps you can:
 - show some example of what you mean
 - describe what is the issue that you are seeing/trying to solve

Regards,
Dario

--=20
<<This happens because I choose it to happen!>> (Raistlin Majere)
-----------------------------------------------------------------
Dario Faggioli, Ph.D, http://about.me/dario.faggioli
Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK)


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