> > > I'm guessing one of the reasons you wanted a > non-RAID controller with > > a write cache was so that if the controller failed, > and the exact same > > model wasn't available to replace it, most of your > pool would still be > > readable with any random controller, modulo risk of > corruption from > > the lost write cache. so...with the slog, you > don't have that, > > because there are magic irreplaceable bits stored > on the slog without > > which your whole pool is useless. > >
Actually I just wanted to get the benefit of increased write cache without paying for the RAID controller... All the "best practice" guides say that using your RAID controller is generally redundant, and you should use RaidZ (or a variant) in most implementations (leaving room for scenarios where hardware mirroring of some of the drives may be better, etc). Telling the RAID controller to export each drive as a single LUN works with most of the RAID controllers our there... but in addition to being painful to configure (on most of the RAID cards), you're paying for RAID hardware logic that goes unused. Also, all the RAID cards (that I've seen) write some sort of magic secret on the drive (even in 1:1 config) that messes with you when you need to replace/move the drives down the road. So how 'bout it hardware vendors? when can we get a PCIe(x8) SAS/SATA controller with an x4 internal port and an x4 external port and 512MB battery backed cache for about $250?? :) Heck, I'd take SATA only if I could get it at a decent price point... While we're at it, I'd also be happy with a PCIe(x4) card with 2 or 4 DIMM slots and a battery back-up that exposes itself as a system drive (ala iRAM, but PCIe not SATA 150) for slog and read cache... say $150 price point? heehee... there is an SSD based option out there, but it has 80GB available, and starts at $2500 (overkill for my requirement) -Matt -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
