[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Calculating real cpu usage of Xen domains correctly!




On 24 Feb 2005, at 21:46, John L Griffin wrote:

3. All the "event_pending(prev)" check in __enter_scheduler() is for is to
say "whoops, an event arrived in the time between when the guest OS
blocked & right now, so I should clear the BLOCKED flag." This is so the domain can be rescheduled at the scheduler's earliest discretion (possibly
immediately).

It's to avoid a wakeup waiting race that could cause the domain to be descheduled for unbounded time despite the fact that it now has work to do (event processing).

But yes, we'd expect that check not to trigger very often in normal circumstances.

 -- Keir



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now.
http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.