On Wed, 29 Jul 2009, Jorgen Lundman wrote:
So, it is slower than the CF test. This is disappointing. Everyone else seems to use Intel X25-M, which have a write-speed of 170MB/s (2nd generation) so perhaps that is why it works better for them. It is curious that it is slower than the CF card. Perhaps because it shares with so many other SATA devices?
Something to be aware of is that not all SSDs are the same. In fact, some "faster" SSDs may use a RAM write cache (they all do) and then ignore a cache sync request while not including hardware/firmware support to ensure that the data is persisted if there is power loss. Perhaps your "fast" CF device does that. If so, that would be really bad for zfs if your server was to spontaneously reboot or lose power. This is why you really want a true enterprise-capable SSD device for your slog.
Bob -- Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
