On Wed, Jun 16, 2010 at 04:44:07PM +0200, Arne Jansen wrote: > Please keep in mind I'm talking about a usage as ZIL, not as L2ARC or main > pool. Because ZIL issues nearly sequential writes, due to the NVRAM-protection > of the RAID-controller the disk can leave the write cache enabled. This means > the disk can write essentially with full speed, meaning 150MB/s for a 15k > drive. > 114000 4k writes/s are 456MB/s, so 3 spindles should do.
You'd still have to flush those caches at the end of each transaction, which would tend to come every few seconds, so you'd need to factor that in. You can definitely do with disk what you can do with SSDs, but not necessarily with the same SWAP (space, wattage and price), and you'd have a more complex system no matter what. Nico -- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
