Re: AW: GNBD multipath with devicemapper? -- possible solution

[Hansjörg Maurer <hansjoerg.maurer@xxxxxx>]

Hi

I did further tests and I am not sure if it is gnbd related.
I did some tests with local ext3 and local gfs filesystem
on rhel4   2.6.9-6.36 and 2.6.9-6.38 with current cvs (RHEL4 tag).
ext3 reads and writes 2000MB in about 13-14s on our new testhardware.
gfs writes it in about 15s and needs about 40 s for reading (even with 
lock_nolock filesystem)

Maybe you can try this on an local RHEL4 gfs filesystem to, in order to 
be sure,
that my initially gnbd problem did not lead you to the wrong direction 
and the problem is gfs related.

nice weekend from munich

hansjörg





Benjamin Marzinski wrote:

> On Thu, Apr 21, 2005 at 07:58:49AM +0200, Hansjörg Maurer wrote:
>  
>
> > Hi
> >
> > thank you very much,
> > Do you have any idea what causes the speed difference between vanilla 
> > and RHEL4 kernel?
> > Should I officially file a bug in bugzilla, or do you take care of the 
> > problem?
> >    
>
> Go ahead and file a bug on gnbd if you are interested in tracking the status
> of this. I'll put it on my list of things to do.
>
> -Ben
>
>  
>
> > Greetings
> >
> >
> > Hansjörg
> >
> >
> >
> >
> >
> >    
> >
> > > I got those numbers on a vanilla 2.6.11 kernel.
> > > Running on a 2.6.9-6.24.EL kernel, I get
> > > 45.6608 MB/sec writes 
> > > 35.8578 MB/sec reads
> > >
> > > Not as pronouced as your numbers, but a noticeable speed difference.
> > >
> > > -Ben
> > >
> > >
> > >      
> > >
> > > > Thank you very much
> > > >
> > > > Hansjörg
> > > >
> > > >  
> > > >
> > > >        
> > > >
> > > > >    
> > > > >
> > > > >          
> > > > --
> > > > _________________________________________________________________
> > > >
> > > > Dr.  Hansjoerg Maurer           | LAN- & System-Manager
> > > >                             |
> > > > Deutsches Zentrum               | DLR Oberpfaffenhofen
> > > > f. Luft- und Raumfahrt e.V.   |
> > > > Institut f. Robotik             |
> > > > Postfach 1116                   | Muenchner Strasse 20
> > > > 82230 Wessling                  | 82234 Wessling
> > > > Germany                         |
> > > >                             |
> > > > Tel: 08153/28-2431              | E-mail: Hansjoerg.Maurer@xxxxxx
> > > > Fax: 08153/28-1134              | WWW: http://www.robotic.dlr.de/
> > > > __________________________________________________________________
> > > >
> > > >
> > > > There are 10 types of people in this world, 
> > > > those who understand binary and those who don't.
> > > >
> > > > --
> > > >
> > > > Linux-cluster@xxxxxxxxxx
> > > > http://www.redhat.com/mailman/listinfo/linux-cluster
> > > >  
> > > >
> > > >        
> > > --
> > >
> > > Linux-cluster@xxxxxxxxxx
> > > http://www.redhat.com/mailman/listinfo/linux-cluster
> > >
> > >
> > >
> > >      
> > --
> > _________________________________________________________________
> >
> > Dr.  Hansjoerg Maurer           | LAN- & System-Manager
> >                               |
> > Deutsches Zentrum               | DLR Oberpfaffenhofen
> > f. Luft- und Raumfahrt e.V.   |
> > Institut f. Robotik             |
> > Postfach 1116                   | Muenchner Strasse 20
> > 82230 Wessling                  | 82234 Wessling
> > Germany                         |
> >                               |
> > Tel: 08153/28-2431              | E-mail: Hansjoerg.Maurer@xxxxxx
> > Fax: 08153/28-1134              | WWW: http://www.robotic.dlr.de/
> > __________________________________________________________________
> >
> >
> > There are 10 types of people in this world, 
> > those who understand binary and those who don't.
> >
> > --
> >
> > Linux-cluster@xxxxxxxxxx
> > http://www.redhat.com/mailman/listinfo/linux-cluster
> >    
>
> --
>
> Linux-cluster@xxxxxxxxxx
> http://www.redhat.com/mailman/listinfo/linux-cluster
>
>  

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