WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [PATCH] Fix xm commands for inactive domains

To: "Daniel P. Berrange" <berrange@xxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] Fix xm commands for inactive domains
From: Ewan Mellor <ewan@xxxxxxxxxxxxx>
Date: Fri, 15 Dec 2006 11:50:26 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 15 Dec 2006 03:50:55 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <20061213171101.GC5429@xxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <20061213153809.GB5429@xxxxxxxxxx> <20061213171101.GC5429@xxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.9i
On Wed, Dec 13, 2006 at 05:11:01PM +0000, Daniel P. Berrange wrote:

> On Wed, Dec 13, 2006 at 03:38:09PM +0000, Daniel P. Berrange wrote:
> > 
> > The commands 'mem-set' 'mem-max' and 'vcpu-set' are all broken when used 
> > against an inactive domain. The backend implementation of these commands
> > typically updates the in-memory config held by XenD, and does a hypercall
> > or xenstore write to update the live guest. Obviously the latter part fails
> > with inactive guests. The changes are also not persisted to disk.
> > 
> > The attached patch ensures that the hypercalls/xenstore writes are not
> > tried for inactive guests. It will also write out the changes to disk
> > so config changes to inactive guests are preserved across XenD restarts.
> > 
> > Normally memory_dynamic_min/max  and online_vcpus are picked up from the
> > running domain state. This doesn't apply for inactive guests, so when 
> > changing config for inactive guests, we also update those 3 parameters to
> > match the new settings. 
> > 
> > So, at the end of all this, I can do:
> > 
> > 1. Define an inactive domain...
> > 
> >   # xm new demo
> >   # xm list demo
> >   Name                                      ID   Mem VCPUs      State   
> > Time(s)
> >   demo                                           410     1                 
> > 0.0
> >   # xm list --long demo | grep mem
> >       (memory 410)
> >       (maxmem 800)
> >       (shadow_memory 0)
> >       (memory_dynamic_min 410)
> >       (memory_dynamic_max 800)
> > 
> > 2. Change its memory config...
> > 
> >   # xm mem-set demo 500
> >   # xm mem-max demo 1000
> >   # xm list --long demo | grep mem
> >       (memory 500)
> >       (maxmem 1000)
> >       (shadow_memory 0)
> >       (memory_dynamic_min 500)
> >       (memory_dynamic_max 1000)
> >   # xm list demo
> >   Name                                      ID   Mem VCPUs      State   
> > Time(s)
> >   demo                                           500     1                 
> > 0.0
> > 
> > 3. Change its cpu config...
> > 
> >   # xm vcpu-set demo 8
> >   # xm list --long demo | grep vcpu
> >       (vcpus 8)
> >       (online_vcpus 8)
> >   # xm list demo
> >   Name                                      ID   Mem VCPUs      State   
> > Time(s)
> >   demo                                           500     8                 
> > 0.0
> > 
> > 4. Start it with new settings...
> > 
> >   # xm start demo
> >   # xm list demo
> >   Name                                      ID   Mem VCPUs      State   
> > Time(s)
> >   demo                                      22   500     8     -b----      
> > 0.7
> > 
> > NB, the patch is structured so there is no functional change for active
> > guests, to minimise risk of regression in this 3.0.4 freeze. I think this
> > is really important to get working in 3.0.4 since inactive domain support
> > is of pretty limited usefullness as it currently stands.  Hopefully in 3.0.5
> > the XenAPI will make it possible to change all aspects of an inactive guest
> > config.
> > 
> >   Signed-off-by: Daniel P. Berrange  <berrange@xxxxxxxxxx>
> 
> There was one final problem I've just also fixed - for some reason the
> SEXPR api to change max memory was calling into XenDomain instead of
> XenDomainInfo directly. This meant it needed a domid - which doesn't
> exist in inactive domain case. So this updated version of the patch also
> fixed SrvDomain.py  to call the XenDomainInfo object it already has 
> directly - this matches the style of the rest of the method in SrvDomain.py
> 
> The attached patch contains my original patch + this SrvDomain.py fix.
> Now, not only does 'xm' work correctly, but libvirt can manage inactive
> domains & their config settings too.
> 
>  Signed-off-by: Daniel P. Berrange  <berrange@xxxxxxxxxx>

Applied, thanks Daniel.  Nice stuff.

Ewan.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>