Just to add a note, that if we do use partitions on the DDN storage then, the partition should be created with first cylinder as 9 and this will make sure that the alignment is optimal.
Thanks Anand On Oct 18, 2007, at 10:11 AM, Brian J. Murrell wrote: > On Thu, 2007-10-18 at 13:02 -0400, Brock Palen wrote: >> >> I did some basics test, 1MDS 1OST 1raid5 (half a xserve raid) Using >> tiobench on 1 client, using no partition table netted about 5MB/s >> faster for streaming read/write. I will scale up my tests though and >> try some other raid configurations. Thanks for the help. > > You could consider using the sgpdd_survey in our iokit. It was > written > specifically to test raw disk throughput and can cover a large > number of > concurrent threads and i/o sizes to show you the characteristics of > your > disk. > > Some disks, such as DDNs specifically (maybe there are others) are > recommended to use without partition tables because the partition > table > at the beginning of the disk interferes with optimal alignment > characteristics of the disk and performance suffers as a result. > > b. > > > _______________________________________________ > Lustre-discuss mailing list > [email protected] > https://mail.clusterfs.com/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
