On Apr 8, 2010, at 8:52 AM, Bob Friesenhahn wrote: > On Thu, 8 Apr 2010, Erik Trimble wrote: >> While that's great in theory, there's getting to be a consensus that 1TB >> 7200RPM 3.5" Sata drives are really going to be the last usable capacity.
I doubt that 1TB (or even 1.5TB) 3.5" disks are being manufactured anymore. These have dropped to the $100 price barrier already. 2TB are hanging out around $150. > Agreed. The 2.5" form factor is rapidly emerging. I see that enterprise > 6-Gb/s SAS drives are available with 600GB capacity already. It won't be > long until they also reach your 1TB "barrier". Yep, seeing some nice movement in this space. >> So, while it's nice that you can indeed seemlessly swap up drives sizes (and >> your recommendation of using 2x7 helps that process), in reality, it's not a >> good idea to upgrade from his existing 1TB drives. > > It would make more sense to add a new chassis, or replace the existing > chassis with one which supports more (physically smaller) drives. While > products are often sold based on their ability to be upgraded, upgrades often > don't make sense. > >> Now, in the Real Near Future when we have 1TB+ SSDs that are 1cent/GB, well, >> then, it will be nice to swap up. But not until then... > > I don't see that happening any time soon. FLASH is close to hitting the wall > on device geometries and tri-level and quad-level only gets you so far. A > new type of device will need to be invented. It is a good idea to not bet against Moore's Law :-) The current state of the art is an 8GB (byte, not bit) MLC flash chip which is 162 mm^2. In the space of a 2.5" disk with some clever packaging you could pack dozens of TB. -- 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
