On 17 Feb 2012, at 17:45, Nathan Dauchy wrote: > James, > > Depending on how often you need the information updated, and how > perfectly accurate it has to be, you may find that just using normal > "find" on a snapshot of the MDT is more efficient. (IIRC that > size-on-mds is relatively close these days.) If you have your MDT on > LVM for making backups (for example), you could also periodically run > your find on the same snapshot.
We generally do have the mdt on LVM however I am adverse to taking snapshots of it as the performance hit while you have a snapshot is pretty severe. And we don't back any of our lustre systems up. > With your "lfs find" approach, I think you will have to decide if you > want to trust the size-on-mds anyway or query the OSTs which will slow > things down a lot. There is more than one way to do it. Given that we run the scan about once a month, If the size-on-mds was relatively up to date then I would love to use it. On our general purpose filesystems running a scan using real stats is not feasible. However I don't have a clue how to get at the size on mdt, If anyone would point me at some documentation then that would be grand. > > -Nathan > > PS: I love the color-coded bar graph approach... very informative in a > compact display! Just in case it wasn't clear agedu is written by Simon Tatham who is also know for PuTTY, I have sent him a few emails and he responds very quickly and he seems a very bright fellow. -- The Wellcome Trust Sanger Institute is operated by Genome Research Limited, a charity registered in England with number 1021457 and a company registered in England with number 2742969, whose registered office is 215 Euston Road, London, NW1 2BE. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
