On Wed, 7 Apr 2010, Edward Ned Harvey wrote:
BTW, does the system *ever* read from the log device during normal operation? Such as perhaps during a scrub? It really would be nice to detect failure of log devices in advance, that are claiming to write correctly, but which are really unreadable.
To make matters worse, a SSD with a large cache might satisfy such reads from its cache so a "scrub" of the (possibly) tiny bit of pending synchronous writes may not validate anything. A lightly loaded slog should usually be empty. We already know that some (many?) SSDs are not very good about persisting writes to FLASH, even after acking a cache flush request.
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
