On 2009-12-01, at 03:30, rishi pathak wrote: > We are in the processes of setting up 2 filesystems using lustre. > The first one will be based on 10K RPM SAS drives (much faster - > scratch space), > Second would be on 1TB SATA drives (slower one - user's home).
Actually, I would suggest the reverse - SAS drives for the smaller home filesystem, and the larger SATA drives for the scratch filesystem. Users need better interactive performance and generally use smaller files, while the scratch filesystem is used by batch jobs that need higher throughput but does not notice higher latency. Depending on how large you want to make your home filesystem, you might consider using RAID-1 instead of RAID-6 to further improve the filesystem performance. > As I can see, there are two options : > 1.Create two separate filesystems with multihomed MDS > 2. A single filesystem with 2 OST pools with different stride > size(one SAS and one SATA based). > Create 2 directories in the lustre FS root by name > 'scratch' & 'home' and set stripe pattern and stripe size > accordingly for scratch(SAS) and home(SATA). > > Any pointers to pros and cons for the above two setup. > Other thing is that we do not want files to be stripped across pool. > Is there anything that would enforce this. Currently it is not possible to use pools to _deny_ access to specific OSTs, though this would be an interesting feature. From your description, I can't see any benefit to having these different OSTs in the same filesystem Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
