[Lustre-discuss] Quota behavior with inactive OSTs

[Johann Lombardi]

On Fri, Apr 20, 2012 at 09:02:06AM -0400, Kevin Hildebrand wrote:
> I have a handful of OSTs temporarily marked inactive because they are
> close to full, and as soon as they are marked inactive, 'lfs quota' stops
> showing their contribution to the total.  Is this the correct behavior?

No, that's not the correct behavior. The problem is that the lustre client relies on the MDS to collect real disk usage from all the OSTs (via Q_GETOQUOTA RPCs). This is different in orion (i.e. 2.4) where it is up to the lustre client to retrieve usage from OSTs directly.

We landed a patch recently (for compatibility with orion) which might help a little bit, see http://review.whamcloud.com/#change,1570. It allows the client to fetch disk usage directly from OSTs if the MDS does not set QIF_SPACE in the reply (that's the case of orion MDS). That said, applying this patch still does not bring you where you want since the 1.8 MDS still replies with QIF_SPACE. To address this, you will have to patch the mds_get_dqblk() function in lustre/quota/quota_master.c not to call mds_get_space().

HTH

Johann
-- 
Johann Lombardi
Whamcloud, Inc.
www.whamcloud.com