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

Re: [Xen-devel] 100 Hz idle timer on domU?

On Monday 23 May 2005 14:51, Ian Pratt wrote:
> > I just built bk-1.1514 (which oddly enough that version I
> > can't find a reference to on bk-bits anymore, was that
> > changeset backed out?)
> It's probably bk renumbering things -- you really need to refer to
> changesets by MD5KEY.

OK, thanks.
> > and I am noticing that domU's cpus are
> > getting timer ticks at 100Hz even when idle.  I know I have
> > observed a "no tick" behavior before.  Was this change intentional?
> I bet I know what this is. Please can you try the following to see if
> it goes away:
> 'bk cset -x428f2c2a_3sOeZVGhQutbJc15aCU9g'

I'll give it a shot right now.  FWIW, I did tack cpu util with the 100 
Hz timer on 12 idle 4-way domU's (on 2 cpu Xeon with HT).
Attached is a text file with the cpu util.  Each cpu burns about 1.5% 
just to maintain the idle domains.  Not sure of the impact of a 
workload running in one of these while many other are idle, but I 
suspect it could be worse than 1.5% (will find out soon).


> ChangeSet@xxxxxxxxxxxxxx, 2005-05-21 13:40:10+01:00,
> cl349@xxxxxxxxxxxxxxxxxxxx
>   Fix e1000 hang during reboot bug.  Kudos to Steven Hand for
> analyzing. time.c:
>     Fix bug in code which sets our one-shot timer when we decide to
> block during
>     the idle loop.
>   Signed-off-by: Christian Limpach <Christian.Limpach@xxxxxxxxxxxx>
> Thanks,
> Ian

Attachment: cpu-12doms.txt
Description: Text document

Xen-devel mailing list



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