Lustre discuss - Sep 2009 - What are the current striping limits?

Dear ListThe excellent wiki:
http://www.inter-mezzo.org/index.php?title=MDS_striping_format

states that
*Note*: Limits for stripe settings are:

   - Maximum striping count for a single file is 160.
   - Maximum striping count for the system is 65532.
   - Minimum striping size is 65536.
   - Result of stripe_size * stripe_count should less than 0xffffffff.


Are these values current? That is current for 1.8

Thanks in anticipation.

Geoff Carrier
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Hello!

On Sep 20, 2009, at 3:51 PM, Geoff Lustre wrote:
> Dear List
> The excellent wiki:
> http://www.inter-mezzo.org/index.php?title=MDS_striping_format
>
> states that
> Note: Limits for stripe settings are:
> 	? Maximum striping count for a single file is 160.
This is still current (work in bug 4424 is changing this).
> 	? Maximum striping count for the system is 65532.
This is current, I think.
> 	? Minimum striping size is 65536.
This is also current (not sure why people would like this to be any  
smaller).
> 	? Result of stripe_size * stripe_count should less than 0xffffffff.
This was changed, and now maximum stripe size could be up to 4G-64k

Bye,
     Oleg

On Sep 20, 2009  15:58 -0400, Oleg Drokin wrote:
> On Sep 20, 2009, at 3:51 PM, Geoff Lustre wrote:
> 
> > Dear List
> > The excellent wiki:
> > http://www.inter-mezzo.org/index.php?title=MDS_striping_format
Also a minor note that the better URL for this would be:

    http://arch.lustre.org/index.php?title=MDS_striping_format

(same page, better domain).
> This is also current (not sure why people would like this to be any  
> smaller).
> 
> > 	? Result of stripe_size * stripe_count should less than 0xffffffff.
> 
> This was changed, and now maximum stripe size could be up to 4G-64k
That is - a single stripe_size can be up to ~4G, regardless of the
stripe_count.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.