Hi Bob, My guess is something like it's single threaded, with each file dealt with in order and requests being serviced by just one or two disks at a time. With that being the case, an x4500 is essentially just running off 7200 rpm SATA drives, which really is nothing special.
A quick summary of some of the figures, with times normalized for 3000 files: Sun x2200, single 500GB sata: 6m25.15s Sun v490, raidz1 zpool of 6x146 sas drives on a j4200: 2m46.29s Sun X4500, 7 sets of mirrored 500Gb SATA: 3m0.83s Sun x4540, (unknown pool - Jorgen, what are you running?): 4m7.13s Taking my single SATA drive as a base, a pool of mirrored SATA is almost exactly twice as quick which makes sense if ZFS is reading the file off both drives at once. The raid pool of SAS drives is quicker again, but for a single threaded request that also seems about right. The random read benefits of the mirror aren't going to take effect unless you run multiple reads in parallel. What I suspect is helping here are the slightly better seek times of the SAS drives, along with slightly higher throughput due to the raid. What might be interesting would be to see the results off a ramdisk or SSD drive. Ross -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
