On Thu, December 23, 2010 22:45, Edward Ned Harvey wrote: >> From: zfs-discuss-boun...@opensolaris.org [mailto:zfs-discuss- >> boun...@opensolaris.org] On Behalf Of Bill Werner >> >> on a single 60GB SSD drive, use FDISK to create 3 physical partitions, a > 20GB >> for boot, a 30GB for L2ARC and a 10GB for ZIL? Or is 3 physical >> Solaris >> partitions on a disk not considered the entire disk as far as ZFS is >> concerned? > > You can do that. Other people have before. But IMHO, it demonstrates a > faulty way of thinking. > > "SSD's are big and cheap now, so I can buy one of these high performance > things, and slice it up!" In all honesty, GB availability is not your > limiting factor. Speed is your limiting factor. That's the whole point > of > buying the thing in the first place. If you have 3 SSD's, they're each > able > to talk 3Gbit/sec at the same time. But if you buy one SSD which is 3x > larger, you save money but you get 1/3 the speed.
Boot, at least, largely doesn't overlap with any significant traffic to ZIL, for example. And where I come from, even at work, money doesn't grow on trees. Sure, three separate SSDs will clearly perform better. They will also cost 3x as much. (Or more, if you don't have three free bays and controller ports.) The question we often have to address is, "what's the biggest performance increase we can get for $500". I considered multiple rotating disks vs. one SSD for that reason, for example. Yeah, anybody quibbling about $500 isn't building top-performance enterprise-grade storage. We do know this. It's still where a whole lot of us live -- especially those running a home NAS. > That's not to say there's never a situation where it makes sense. Other > people have done it, and maybe it makes sense for you. But probably not. Yeah, okay, maybe we're not completely disagreeing. -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
