Hitachi GST whacks Seagate in the Savvios
Ultrastar is new shining light in enterprise SFF market
Updated Hitachi GST is taking on Seagate by launching a fast and small hard drive that matches the Savvio's capacity and SAS 2 interface but has four times the cache.
In the enterprise 2.5-inch drive market Seagate has a 15,000rpm Savvio 15K.2 drive - two meaning second generation - that offers 73 and 146GB capacity points and has a 16MB cache.
Hitachi GST, the ambitious number three in the hard drive industry, has launched its Ultrastar C15K147, also spinning at 15,000rpm. You get 147GB, 1 more than Seagate, and a 64MB cache with the SAS 2 (6Gbit/s) interface. There's an encryption option and the usual stuff about efficient power management and vibration cancelling and so forth, but the gist of it is that HGST has got a drive that matches Savvio 15K.2 speed and capacity and quadruples its cache.
HGST has also been busy with its Ultrastar brand in the 3.5-inch form factor space. There's a 600GB 15K600 product, which also spins at 15,000rpm and has a 64MB cache. It has either an SAS 2 or a 4Gbit/s Fibre Channel interface.
HGST's target is Seagate's equivalent product, the Cheetah 15K.7. It offers 600GB from its 15,000rpm platters, has a 4gig FC interface and a 16MB cache. So what HGST is bringing as extras to the table are the 6gig SAS interface and a much bigger cache.
Hitachi GST is continuing to develop and extend its product range. It has a solid state drive coming, courtesy of a deal with Intel, and developments like these two Ultrastar drives increase its strength as a drive supplier. If it manages to keep up with Seagate and WD in the coming transition from perpendicular magnetic recording to bit patterning or heat-assisted magnetic recording, then it will have strengthened its credibility as a supplier enormously.
Update: This story has been updated to include a discussion of Seagate's 15K.2 146GB Savvio drive. ®
Re: What a waste
Write cache - yes. It is definitely turned off by most RAID controllers.
Read cache AFAIK usually is not.
Frankly, 64M vs 16M is not likely to make a hell lot of difference in most production deployments. It will make a difference only if you have a clued up sysadmin who have optimised the layout by hand or if you have spent a hefty wad of cash on a system that does that for you. That is the minority of sites. The majority will just stick the lot in a driver array and format it which means that metadata (journals, indexes, allocation tables) and data will end up on the same disk (courtesy of flat RAID5/6). As a result any data access to a single disk will always be accompanied by some metadata access which together will thrash the cache out to the point where it is useless.
What a waste.
You do realize that most enterprise drives are in a raid array and have the on drive cache turned off as a risk reduction measure, right? When drives start coming with battery backed cache let me know.
Grenade, for the monkeys that like to juggle with the pins out.
146GB SAvvio 15K.2 does exist
I've been sent this mail:- "Have another look, 146-15k Savvio 15k.2 is there. I got a couple hundred of 'em, helping me do profit since April 2009."
I'm checking with Seagate because it's invisible on the web site.