On Nov 23, 2006 22:39 -0700, Lee Ward wrote: > On Thu, 2006-11-23 at 15:03 -0700, Andreas Dilger wrote: > > For an apples-apples comparison, it would be possible to deactivate 160 OSTs > > (one per OSS) on MDS via "for N in ... ;do lctl --device N deactivate;done" > > and then run the SSF and FPP jobs again. This will limit the FPP jobs to > > 160 OSTs (like the SSF). It might also be useful to disable 161 OSTs (leave > > 159 active) to avoid the aliasing in the SSF case, or alternately have > > clients each write 7MB chunk sizes or something. > > For our formal testing, we have in our scripts a section that precreates > files, locating them on specific OSTs. Would that be a suitable > alternative to this reconfiguration of lustre you suggest? What you > suggest is possible, of course. I would just rather not deviate our > process without a good reason.
Sure, precreating files on, say, the first 160 OSTs in a round-robin manner for all of the client processes for FPP, and similarly forcing the one SSF file to be created starting on ost_idx 0 will use the same 160 OSTs. Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc. _______________________________________________ Lustre-devel mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-devel
