From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: Implement 3-level event channel routines in Linux.
Date: Thu, 3 Jan 2013 12:12:42 +0000
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On 03/01/13 12:09, Wei Liu wrote:
>
>>> For both cases, what do you have in mind for the metric that used to
>>> trigger the switch? How much RAM / how many CPUs is the threshold?
>> No idea. At what point are we running out of the events?
> In practice, if you have hundreds or thousands of guests running you're
> likely of running out of event channels. I presume host capable of doing
> this has lots of RAM and CPUs...
>
>
> Wei.

Yes, but the per-cpu stacks are still a fixed size.  Xen uses 4 (and a 
half-ish) pages.  Linux I would guess is similar.

~Andrew