On Apr 8, 2010, at 3:23 PM, Tomas Ögren wrote: > On 08 April, 2010 - Abdullah Al-Dahlawi sent me these 12K bytes: > >> Hi Richard >> >> Thanks for your comments. OK ZFS is COW, I understand, but, this also means >> a waste of valuable space of my L2ARC SSD device, more than 60% of the space >> is consumed by COW !!!. I do not get it ? > > The rest can and will be used if L2ARC needs it. It's not wasted, it's > just a number that doesn't match what you think it should be.
Another way to look at it is: all cache space is "wasted" by design. If the backing store for the cache were performant, there wouldn't be a cache. So caches waste space to gain performance. Space, dependability, performance: pick two. -- richard ZFS storage and performance consulting at http://www.RichardElling.com ZFS training on deduplication, NexentaStor, and NAS performance Las Vegas, April 29-30, 2010 http://nexenta-vegas.eventbrite.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
