David Magda wrote: > On Wed, June 16, 2010 10:44, Arne Jansen wrote: >> David Magda wrote: >> >>> I'm not sure you'd get the same latency and IOps with disk that you can >>> with a good SSD: >>> >>> http://blogs.sun.com/brendan/entry/slog_screenshots > [...] >> 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. > > Yes, I understood it as suck, and that link is for ZIL. For L2ARC SSD > numbers see: > > http://blogs.sun.com/brendan/entry/l2arc_screenshots >
oops, sorry, I should at least scrolled down a bit on your link... Nevertheless I don't find it improbable to reach numbers like that for a proper RAID-setup. Of cause it will take more space and power. Maybe someone has done some testing on this. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
