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] Remus and Kemari...

To: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-devel] Remus and Kemari...
From: Gilberto Nunes <gilberto.nunes@xxxxxxxxxxxxxxx>
Date: Thu, 21 Jan 2010 08:57:37 -0200
Delivery-date: Thu, 21 Jan 2010 02:57:27 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20100121104327.GQ2861@xxxxxxxxxxx>
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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Organization: Selbetti Gestão de Documentos
References: <4B4F0581.30005@xxxxxxxxxxxxxxx> <201001210840.35666.gilberto.nunes@xxxxxxxxxxxxxxx> <20100121104327.GQ2861@xxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.12.2 (Linux/2.6.27.42-0.1-default; KDE/4.3.2; i686; ; )

Em Quinta-feira 21 Janeiro 2010, às 08:43:27, Pasi Kärkkäinen escreveu:

> On Thu, Jan 21, 2010 at 08:40:35AM -0200, Gilberto Nunes wrote:

> > Em Quinta-feira 21 Janeiro 2010, às 08:16:55, você escreveu:

> >

> > Hi Pasi

> >

> > > On Thu, Jan 21, 2010 at 08:12:21AM -0200, Gilberto Nunes wrote:

> > > > Em Quarta-feira 20 Janeiro 2010, às 22:20:17, Brendan Cully escreveu:

> > > >

> > > > Hi Brendan...

> > > >

> > > > > On Thursday, 14 January 2010 at 09:52, gilberto nunes wrote:

> > > > > > I installed the Remus but had some problems.

> > > > > > He leaves the VM very slow. I'm using a partition with DRBD /

> > > > > > LVM. May even be that you say that has many layers (DRBD / LVM)

> > > > > > that can influence on performance.

> > > > > > But the interesting thing is that when Remus is not running the

> > > > > > VM is light even with 512M of memory. And look what I'm talking

> > > > > > about a Windows 2003 Standard Edition.

> > > > > > The Remus to stop working inexplicably (at least for me)

> > > > > > and let the VM's started in a state of the two nodes ...

> > > > >

> > > > > It's taken me a while to get Xen unstable running again, but now

> > > > > that I have I can't reproduce any of these problems with an XP

> > > > > guest. It remains responsive while Remus is running, and doesn't

> > > > > fail over unless I kill it.

> > > >

> > > > Right

> > > >

> > > > > Disk access isn't likely to make a huge performance difference

> > > > > (although I should say, simply parking a Remus VM on top of DRBD is

> > > > > not safe, since there is no way of rolling back changes that have

> > > > > been written since the most recent checkpoint).

> > > >

> > > > What you suggest... NFS!

> > > >

> > > > > It sounds like your network

> > > > > link between the primary and backup is either low capacity or flaky

> > > > > in some way, or you have a loaded dom0.

> > > >

> > > > My network between primary and backup server is a dedicate network,

> > > > make with a dedicate fast ethernet switch...

> > >

> > > Not sure if Fast Ethernet is enough for Remus syncing?

> >

> > Well, I try too with crossover network cable, in Giga Ethernet, but I

> > have the same...

> >

> > > > I do not understand wath you say about that "I have a loaded dom0".

> > > > On fact, Xen always have a loaded dom0, right!

> > >

> > > I bet he meant "do you have high load on dom0", aka do you have high

> > > cpu usage in dom0? Try running "xm top" to figure out. And also normal

> > > "top" in dom0.

> >

> > Ok... I run xm top and get this:

> >

> > NAME

> > Domain-0

> >

> > STATE

> > -----r

> >

> > CPU(sec)

> > 135

> >

> >

> > CPU(%)

> > 0.6

>

> So it's not using much CPU.

right... indeed I have just one VM running right now... My server has 8G amount of memory and it is a Intel Xeon E3113 3.00 GHZ

>

> > MEM(k)

> > 7226368

> >

> > MEM(%)

> > 86.2

>

> Did you configure dom0_mem= for Xen?

Yes! It's dangerous or not!!

>

> See:

> http://wiki.xensource.com/xenwiki/XenBestPractices

>

> Or is there something in dom0 using all the memory for real?

no... all clean... :)

> Run "top" in dom0, and sort by memory usage by pressing shift+m.

>

> > MAXME(k)

> > no limit

> >

> > MAXMEM(%)

> > n/a

> >

> > VCPUS

> > 2

> >

> > Something wrong!!!

> >

> > >>> I'd recommend using single-processor dom0 and guest to start with,

> > >>> and

> > >>>

> > > > > pinning the VCPUs to their own separate physical cores.

> > > >

> > > > I see. But how I do this!! I am a newbie. If you can point some ways

> > > > to me, I'll appreciate...

> > >

> > > See:

> > > http://wiki.xensource.com/xenwiki/XenCommonProblems

> > >

> > > There's a chapter called "How can I limit the number of vcpus my dom0

> > > has?" and "Can I dedicate a cpu core (or cores) only for dom0?"

> >

> > I see... However, this procedure do not take alway the beneficity of

> > multi- core processors to my VM's!!!!

>

> You can still use multiple cores on your VMs.

>

> If you don't want to dedicate a core only for dom0, at least configure the

> domain weights so that dom0 is guaranteed to get enough CPU time.

So, in theoretical way, Remus would running properly with this adjust right! (sorry, I using now KDE 4 on opensuse, and I cannot yet configure my keyboard proerly, so the dor question go always from my board...rsrsrsr...)

Thanks for all....

>

> -- Pasi

>

>

> _______________________________________________

> Xen-devel mailing list

> Xen-devel@xxxxxxxxxxxxxxxxxxx

> http://lists.xensource.com/xen-devel

>


--

Gilberto Nunes Ferreira

TI

Selbetti Gestão de Documentos

Telefone: +55 (47) 3441-6004

Celular: +55 (47) 8861-6672

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
<Prev in Thread] Current Thread [Next in Thread>