On Mon, Jul 20, 2009 at 05:44, F. Wessels<no-re...@opensolaris.org> wrote: > Also in reply to the previous email by Will. > > Can anyone shed more light on the combination lsi sas hba , the lsisasx36 > expander chip (or it's relatives) and sata disks. > I'm investigating a migration from discrete channels (like in the thumper) to > a multiplexed solution via a sas expander. > I'm aware that there's a penalty but for my workload that's acceptable. Only > when a wide sas port (4 links) is used, which should result in a theoretical > throughput of 1.2GB/s. But Will reported only 300MB/s, which corresponds to a > single link. That's not what I intended to report. I saw 400 MB/s of write I/O to my six-disk mirrored zpool, and a little over 300 MB/s read. However, the write I/O is reported as half that because it's a mirrored setup, so the userspace app writes 200 MB in a second and the disks have to write that twice in the same period.
In short, I have seen more than 300 MB/s over a SAS expander. I just don't have enough non-production disks to show much more than that. Will _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
