Re: [Xen-devel] Xen cpu usage limting - Brian Wolfe - com.xensource.lists.xen-devel

34 messages in com.xensource.lists.xen-develRe: [Xen-devel] Xen cpu usage limting

From	Sent On	Attachments
Brian Wolfe	16 Apr 2004 09:39
Keir Fraser	16 Apr 2004 09:47
Rolf Neugebauer	16 Apr 2004 09:53
Brian Wolfe	16 Apr 2004 10:14
Mark Williamson	16 Apr 2004 10:17
Keir Fraser	16 Apr 2004 10:19
Mark Williamson	16 Apr 2004 10:32
Brian Wolfe	16 Apr 2004 10:52
Ian Pratt	16 Apr 2004 12:13
Brian Wolfe	16 Apr 2004 15:46
Mark Williamson	19 Apr 2004 08:39
Brian Wolfe	19 Apr 2004 10:26
Mark Williamson	19 Apr 2004 10:34
Brian Wolfe	19 Apr 2004 11:57
I RATTAN	20 Apr 2004 08:43
Borut Mrak	20 Apr 2004 09:27
I RATTAN	20 Apr 2004 11:01
Rolf Neugebauer	20 Apr 2004 11:22
I RATTAN	20 Apr 2004 17:24
Neugebauer, Rolf	20 Apr 2004 17:45
I RATTAN	21 Apr 2004 08:28
Mark Williamson	21 Apr 2004 09:05
I RATTAN	21 Apr 2004 10:21
Rolf Neugebauer	21 Apr 2004 10:40
I RATTAN	21 Apr 2004 19:27
I RATTAN	22 Apr 2004 08:07
Kip Macy	27 Apr 2004 11:55
Ian Pratt	27 Apr 2004 17:27
Kip Macy	27 Apr 2004 18:24
Ian Pratt	27 Apr 2004 19:15
Nuno Silva	27 Apr 2004 19:22
Keir Fraser	27 Apr 2004 23:52
Kip Macy	15 May 2004 17:24
Kip Macy	31 May 2004 13:38

Subject:	Re: [Xen-devel] Xen cpu usage limting
From:	Brian Wolfe (bri...@terrabox.com)
Date:	04/16/2004 10:14:02 AM
List:	com.xensource.lists.xen-devel

Well, I'm not certain exactly to be honest. the filesystems are nfs mounted. the domain that was eating everything up was stuck in a nasty php infinite loop. I'll see if I can do a bit more tracking and report back. It may very well have been a network saturation problem.( gotta locate a few more compatible cards. and get gig-e backside for the nfs mounts.)

I was also wondering if there is a way to assign a percentage of cpu time to a domain. Eg guarantee domain 3 gets 25% of the cpu time no matter how many other domains are in there, or how much cpu time they want.

Also, I assume that xc_dom_control list right most column shows the amount of time each domain has eaten up?

Rolf Neugebauer said:

Hi Brian,

which version of Xen/Xenolinux are you using? the scheduler implementation changed from 1.2 to 1.3-unstable.

On Fri, 2004-04-16 at 17:40, Brian Wolfe wrote:

Is it possible? How? (looked for documentation, but I didn't see any.) I did see xen_cpuperf, but I can't get any real information from there either. 8-(

I have 8 domains (including domain-0) runing on the server. If one goes to 100% cpu time, the system bogs. I'd like to be able to ensure that each instance can't keep the rest from runing...

This should definitely not happen!!! Could you provide a little more detail on what is running in the different domains?

In 1.2 the scheduler is a weighted proportional share scheduler (BVT) and by default all domains get the same weight and therefore should get the same share.

in 1.3 you have a boot-time choice between schedulers, BVT (same as in 1.2, Atropos (a soft real time scheduler based on EDF)

I have just tested with 1.3-unstable, four domains on a dual processor machine (two domains per CPU) and BVT as the scheduler and they happily share the CPU 50/50 if both run the equivalent of a while(1) loop.