On Mar 6, 2010, at 1:02 PM, Edward Ned Harvey wrote: > Recently, I’m benchmarking all kinds of stuff on my systems. And one > question I can’t intelligently answer is what blocksize I should use in these > tests. > > I assume there is something which monitors present disk activity, that I > could run on my production servers, to give me some statistics of the block > sizes that the users are actually performing on the production server. And > then I could use that information to make an informed decision about block > size to use while benchmarking. > > Is there a man page I should read, to figure out how to monitor and get > statistics on my real life users’ disk activity?
It all depends on how they are connecting to the storage. iSCSI, CIFS, NFS, database, rsync, ...? The reason I say this is because ZFS will coalesce writes, so just looking at iostat data (ops versus size) will not be appropriate. You need to look at the data flowing between ZFS and the users. fsstat works for file systems, but won't work for zvols, as an example. -- richard ZFS storage and performance consulting at http://www.RichardElling.com ZFS training on deduplication, NexentaStor, and NAS performance http://nexenta-atlanta.eventbrite.com (March 16-18, 2010) _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
