On Wed, Dec 05, 2007 at 06:12:18PM -0600, Al Hopper wrote: > > I don't think you'll see any worthwhile improvement. For a ZIL > device, you really need something like a (small) SAS 15k RPM 3.5" > drive - which will sustain 700 to 900 IOPS (my number - open to > argument) - or a RAM disk or one of these [1]. > > 10K RPM SCSI disks will get (best case) 350 to 400 IOPS. Remember, > the main issue with legacy SCSI is that (SCSI) commands are sent > 8-bits wide at 5Mbits/Sec - for backwards compatibility. You simply > can't send enough commands over a SCSI bus to busy out a modern 10k > RPM SCSI drive.
Ah, ok then. Thanks for the detailed explanation Al, that was very helpful. > PS: LsiLogic just updated their SAS HBAs and have a couple of products > very reasonably priced IMHO. Combine that with a (single ?) Fujitsu > MAX3xxxRC (where xxx represents the size) and you'll be wearing a big > smile every time you work on a system so equipped. > > Tell Santa that you want an LsiLogic SAS HBA and some SAS disks for > Xmas! :) Santa came early this year. :) The whole reason I'm able to get these SATA disks into my Ultra80 is because I bought an LSI SAS3080X and 4-lane SAS to 4-sata cable. ;) ($60 including shipping, not a bad deal at all!!) I wasn't sure what I was going to do with the other 4 channels, for the time being nothing as I'm now completely broke. :) A nice SAS enlosure would be a nice addition to this setup I think. Maybe a couple of those Fujitsu disks would be nice. > [1] Finally, someone built a flash SSD that rocks (and they know how > fast it is judging by the pricetag): > http://www.tomshardware.com/2007/11/21/mtron_ssd_32_gb/ > http://www.anandtech.com/storage/showdoc.aspx?i=3167 Uhm, holy crap. I want one of those for my laptop now. I only have a 40G in there, so a 32G mtron would be perfect. ;) Now, the price might be an issue however. ;) -brian -- "Perl can be fast and elegant as much as J2EE can be fast and elegant. In the hands of a skilled artisan, it can and does happen; it's just that most of the shit out there is built by people who'd be better suited to making sure that my burger is cooked thoroughly." -- Jonathan Patschke _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
