From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: Credit scheduler Date: Wed, 27 Jun 2007 02:17:32 +0100 Message-ID: References: <062720070109.4497.4681B8BB000E2A1E000011912207001641CCCCCC050E9F@comcast.net> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0991642998==" Return-path: In-Reply-To: <062720070109.4497.4681B8BB000E2A1E000011912207001641CCCCCC050E9F@comcast.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Mime-version: 1.0 Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: pak333@comcast.net, xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --===============0991642998== Content-type: multipart/alternative; boundary="B_3265755453_7089961" > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3265755453_7089961 Content-type: text/plain; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Are these all Windows HVM guests? And do you exclude domain0 when you count the number of VMs in your system (so it=B9s actually 4 user VMs + domain0 VM)= ? How did you come up with the 3us figure =8B some kind of in-guest tracing, or using xentrace, or by some other means? Does the problem still happen if you run 2 cpu-intensive VMs instead of 3? -- Keir On 27/6/07 02:09, "pak333@comcast.net" wrote: >=20 > I have 4 physical cpus (2 dual core sockets) and the IO workload is loads= im > with 500 users >=20 > Thanks > -Prabha >=20 >=20 > -------------- Original message ---------------------- > From: Keir Fraser >> > How many physical CPUs do you have, and what is the IO workload that o= ne of >> > the VMs is running? >> >=20 >> > -- Keir >> >=20 >> > On 26/6/07 22:33, "pak333@comcast.net" wrote: >> >=20 >>> > > Hi >>> > > =20 >>> > > I have noticed that VMs are typically spending 3 microsecs or less >>> before they >>> > > are being prempted. I thought that the credit schduler time slice w= as 30 >>> ms. I >>> > > have 4 VMs running and they are all cpu intensive except for 1 (whi= ch is IO >>> > > intensive) but having a VM spend max 3 micro secs before being kick= ed out >>> > > seems strange. >>> > > =20 >>> > > Is there something else going on that i am not aware of. Is the tim= e >>> slice >>> > > really 30 millisecs? I am using default parameters of the credit >>> scheduler. >>> > > =20 >>> > > Thanks >>> > > -Prabha >>> > > =20 >>> > >=20 >>> > >=20 >>> > > _______________________________________________ >>> > > Xen-devel mailing list >>> > > Xen-devel@lists.xensource.com >>> > > http://lists.xensource.com/xen-devel >> >=20 >> >=20 >=20 >=20 >=20 > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel --B_3265755453_7089961 Content-type: text/html; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Re: [Xen-devel] Credit scheduler Are t= hese all Windows HVM guests? And do you exclude domain0 when you count the n= umber of VMs in your system (so it’s actually 4 user VMs + domain0 VM)= ? How did you come up with the 3us figure — some kind of in-guest trac= ing, or using xentrace, or by some other means?

Does the problem still happen if you run 2 cpu-intensive VMs instead of 3?<= BR>
 -- Keir

On 27/6/07 02:09, "pak333@comcast.net" <pak333@comcast.net>= wrote:

<= SPAN STYLE=3D'font-size:10.0px'>
I have 4 physical cpus (2 dual core sockets) and the IO workload is loadsim= with 500 users

Thanks
-Prabha


 -------------- Original message ----------------------
From: Keir Fraser <keir@xensource.com>
> How many physical CPUs do you have, and what is the IO workload that o= ne of
> the VMs is running?
>
>  -- Keir
>
> On 26/6/07 22:33, "pak333@comcast.net" <pak333@comcast.ne= t> wrote:
>
> > Hi
> >  
> > I have noticed that VMs are typically spending 3 microsecs or les= s before they
> > are being prempted. I thought that the credit schduler time slice= was 30 ms. I
> > have 4 VMs running and they are all cpu intensive except for 1 (w= hich is IO
> > intensive) but having a VM spend max 3 micro secs before being ki= cked out
> > seems strange.
> >  
> > Is there something else going on that i am not aware of. Is the t= ime slice
> > really 30 millisecs? I am using default parameters of the credit = scheduler.
> >  
> > Thanks
> > -Prabha
> >  
> >
> >
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@lists.xensource.com
> > http://lists.xenso= urce.com/xen-devel
>
>


_____________________________________= __________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/x= en-devel

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