On May 22, 2008, at 19:54, Richard Elling wrote: > The Adaptive Replacement Cache > (ARC) uses main memory as a read cache. But sometimes > people want high performance, but don't want to spend money > on main memory. So, the Level-2 ARC can be placed on a > block device, such as a fast [solid state] disk which may even > be volatile.
The remote-disk cache makes perfect sense. I'm curious if there are measurable benefits for caching local disks as well? NAND-flash SSD drives have good 'seek' and slow transfer, IIRC, but that might still be useful for lots of small reads where seek is everything. I'm not quite understanding the argument for a being read-only so it can be used on volatile SDRAM-based SSD's, though. Those tend to be much, much more expensive than main memory, right? So, why would anybody buy one for cache - is it so they can front a really massive pool of disks that would exhaust market-available maximum main memory sizes? -Bill ----- Bill McGonigle, Owner Work: 603.448.4440 BFC Computing, LLC Home: 603.448.1668 [EMAIL PROTECTED] Cell: 603.252.2606 http://www.bfccomputing.com/ Page: 603.442.1833 Blog: http://blog.bfccomputing.com/ VCard: http://bfccomputing.com/vcard/bill.vcf _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
