On Sat, 17 Apr 2010, Dave Vrona wrote:
1) Mirroring. Leaving cost out of it, should ZIL and/or L2ARC SSDs be mirrored ?
Mirroring the intent log is a good idea, particularly for ZFS versions which don't support removing the intent log device.
2) ZIL write cache. It appears some have disabled the write cache on the X-25E. This results in a 5 fold performance hit but it eliminates a potential mechanism for data loss. Is this valid? If I can mirror ZIL, I imagine this is no longer a concern?
It is not necessary to disable the write cache if the device responds correctly to cache flush requests. The intent log is flushed frequently. Previously some have reported (based on testing) that the X-25E does not flush the write cache reliably when it is enabled. It may be that some X-25E versions work better than others.
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
