On 6/19/10 3:56 AM, Arne Jansen wrote:
while thinking about using the OCZ Vertex 2 Pro SSD (which according to spec page has supercaps built in) as a shared slog and L2ARC device
IMO it might be better to use the smallest (50GB, maybe overprovisioned down to ~20GB) Vertex 2 Pro as slog and a much cheaper SSD (X25-M) as L2ARC.
But if 90% of the device are nearly statically allocated, the devices possibilities for wear-leveling are very restricted. If the ZIL is heavily used, the same 10% of the device get written over and over again, reducing the life span by 90%.
As Bob Friesenhahn said, you're assuming dynamic wear leveling but modern SSDs also use static wear leveling, so this problem doesn't exist. (Note that in this context the terms "dynamic" and "static" may not mean what you think they mean.)
Wes Felter _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
