On Tue, 2010-04-06 at 19:43 -0400, Kyle McDonald wrote: > On 4/6/2010 3:41 PM, Erik Trimble wrote: > > On Tue, 2010-04-06 at 08:26 -0700, Anil wrote: > > > >> Seems a nice sale on Newegg for SSD devices. Talk about choices. What's > >> the latest recommendations for a log device? > >> > >> http://bit.ly/aL1dne > >> > > The Vertex LE models should do well as ZIL (though not as well as an > > X25-E or a Zeus) for all non-enterprise users. > > > > The X25-M is still the best choice for a L2ARC device, but the Vertex > > Turbo or Cosair Nova are good if you're on a budget. > > > > If you really want an SSD a boot drive, or just need something for > > L2ARC, the various Intel X25-V models are cheap, if not a really great > > performers. I'd recommend one of these if you want an SSD for rpool, or > > if you need a large L2ARC for dedup (or similar) and can't afford > > anything in the X25-M price range. You should also be OK with a Corsair > > Reactor in this performance category. > > > > > What about if you want to get one that you can use for both the rpool, > and ZIL (for another data pool?) > What if you want one for all 3 (rpool, ZIL, L2ARC)?? > > -Kyle >
It all boils down to performance and the tradeoffs you are willing to make. For good ZIL, you want something that has a very high IOPS rating (50,000+ if possible, 10,000+ minimum, particularly when writing small chunks). For L2ARC, you are more concerned with total size/capacity, and modest IOPS (3000-10000 IOPS, or the ability to write at least 100Mb/s at 4-8k write sizes, plus as high as possible read I/O). For rpool use, you don't really care about performance so much, as it's almost exclusively read-only (one should generally not configure a swap device on an SSD-based rpool). You could probably live with an X25-M as something to use for all three, but of course you're making tradeoffs all over the place. -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800) _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
