On 2009-10-30, at 05:21, Arne Wiebalck wrote: > We're currently experimenting with Lustre and small files (<=1MB) > and some questions came to mind: > > - will writing files that are smaller than the stripe_size and that > are written to a fully striped directory create objects on more > than 1 OST?
The striping is set at file creation time, before any information is known about how much data will go into the file. > - what would be the main options to tune in order get the best out > of Lustre for small files? (If the answer to the 1st question is > 'yes', then 'avoid striping' would be a first candidate, I guess ;) Right - wide striping should only be used when it is known that the file size will be very large and/or accessed by many nodes at one time. Secondly, using RAID-1+0 OSTs instead of RAID-5/6 will definitely also improve performance, since there is RAID parity overhead for writing small chunks of data to disk. 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
