Re: AW: skip raid5 reconstruction

Re: AW: skip raid5 reconstruction

[Ming Zhang]

Thx.

So it looks like mkraid might do this.

With this hint, I googled the --danferous-no-resync and try to do this

# mdadm --create /dev/md1 --level=5 --assume-clean --raid-
devices=4 /dev/sdf /dev/sdg /dev/sdh /dev/sdi

But then i ran some io and use iostat to find that only 3 devices has io
request and the parity disk has no disk activity at all. so this will be
a skewed data for me.

Ming



On Tue, 2005-07-05 at 19:26 +0200, Lord Hess wrote:
>  kkraid -R --dangerous-no-resync /dev/md..
> 
> Regards,
> 
> Lord
> 
> Certon systems GmbH
> Hans-Bunte-Str. 8 - 10
> 69123 Heidelberg
> Tel:  +49 6221 549810
> Fax: +49 6221 549809
> http://www.certon.de
> mail to: hess@certon.de
> -----Ursprüngliche Nachricht-----
> Von: linux-raid-owner@vger.kernel.org
> [mailto:linux-raid-owner@vger.kernel.org] Im Auftrag von Ming Zhang
> Gesendet: Dienstag, 5. Juli 2005 19:23
> An: Linux RAID
> Betreff: skip raid5 reconstruction
> 
> Hi folks
> 
> I am testing some HW performance with raid5 with 2.4.x kenrel.
> 
> It is really troublesome every time I create a raid5, wait 4 hours for
> reconstruction, and then test some data and then recreate another one
> and wait again. I wonder if there is any hack or option available to
> create a raid5 without reconstruct the parity disk. I just have interest
> to test the performance so do not care about data correctness at this
> stage.
> 
> Thanks!
> 
> 
> Ming
> 
> 
> 
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
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> 

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Re: AW: skip raid5 reconstruction

[Ming Zhang]

On Tue, 2005-07-05 at 13:44 -0400, Ming Zhang wrote:
> Thx.
> 
> So it looks like mkraid might do this.
I tried mkraid and it works. 

Thanks a lot!

Ming

> 
> With this hint, I googled the --danferous-no-resync and try to do this
> 
> # mdadm --create /dev/md1 --level=5 --assume-clean --raid-
> devices=4 /dev/sdf /dev/sdg /dev/sdh /dev/sdi
> 
> But then i ran some io and use iostat to find that only 3 devices has io
> request and the parity disk has no disk activity at all. so this will be
> a skewed data for me.
> 
> Ming
> 
> 
> 
> On Tue, 2005-07-05 at 19:26 +0200, Lord Hess wrote:
> >  kkraid -R --dangerous-no-resync /dev/md..
> > 
> > Regards,
> > 
> > Lord
> > 
> > Certon systems GmbH
> > Hans-Bunte-Str. 8 - 10
> > 69123 Heidelberg
> > Tel:  +49 6221 549810
> > Fax: +49 6221 549809
> > http://www.certon.de
> > mail to: hess@certon.de
> > -----Ursprüngliche Nachricht-----
> > Von: linux-raid-owner@vger.kernel.org
> > [mailto:linux-raid-owner@vger.kernel.org] Im Auftrag von Ming Zhang
> > Gesendet: Dienstag, 5. Juli 2005 19:23
> > An: Linux RAID
> > Betreff: skip raid5 reconstruction
> > 
> > Hi folks
> > 
> > I am testing some HW performance with raid5 with 2.4.x kenrel.
> > 
> > It is really troublesome every time I create a raid5, wait 4 hours for
> > reconstruction, and then test some data and then recreate another one
> > and wait again. I wonder if there is any hack or option available to
> > create a raid5 without reconstruct the parity disk. I just have interest
> > to test the performance so do not care about data correctness at this
> > stage.
> > 
> > Thanks!
> > 
> > 
> > Ming
> > 
> > 
> > 
> > 
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > 
> 

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