OMG, Rich, that did help and solved all my confusion and now I can go to sleep...
So now I have to consider Sun and EMC vs Intel in my home $ spending?! Forget it, Lenovo it is! at least my folks get a cut. Goodnight! best, z ----- Original Message ----- From: "Richard Elling" <richard.ell...@sun.com> To: "Scott Laird" <sc...@sigkill.org> Cc: "JZ" <j...@excelsioritsolutions.com>; "Orvar Korvar" <knatte_fnatte_tja...@yahoo.com>; <zfs-discuss@opensolaris.org>; "Peter Korn" <peter.k...@sun.com> Sent: Friday, January 09, 2009 1:09 AM Subject: Re: [zfs-discuss] ZFS + OpenSolaris for home NAS? > Scott Laird wrote: >> Today? Low-power SSDs are probably less reliable than low-power hard >> drives, although they're too new to really know for certain. Given >> the number of problems that vendors have had getting acceptable write >> speeds, I'd be really amazed if they've done any real work on >> long-term reliability yet. > > Eh? Flash has been around for well over 25 years and the > technology is well understood. Trivia: Sun has been shipping > flash memory for nearly its entire history. What hasn't happened > until relatively recently is that the vendors married high density > flash with a decent controller which expects and manages failures -- > like the disk drive guys did 20 years ago. It occurs to me that > you might be too young to remember that format(1m) was the > tool used to do media analysis and map bad sectors before those > smarts were moved onto the disk ? ;-) Why, we used to have to > regularly scan the media, reserve spare cylinders, and map out > bad sectors in the snow, walking uphill, in our bare feet because > shoes hadn't been invented yet... ;-) > >> Going forward, SSDs will almost certainly >> be more reliable, as long as you have something SMART-ish watching the >> number of worn-out SSD cells and recommending preemptive replacement >> of worn-out drives every few years. That should be a slow, >> predictable process, unlike most HD failures. >> > > I think you will find that failures can still be catastrophic. > But from a typical reliability analysis, the SSDs will be more > reliable than HDDs. The enterprise SSDs have DRAM > front-ends and plenty of spare cells to accommodate expected > enterprise use. FWIW, I expect an MTBF of 3-4M hours for > enterprise SSDs as compared to 1.6M hours for a top-tier > enterprise HDD. More worrying is the relative newness of the > firmware... but software reliability is a whole different ballgame. > > Rumor was that STEC won one of the Apple contracts > http://webfeet.sp360hosting.com/Lists/Research%20News/DispForm.aspx?ID=32 > STEC also supplies Sun and EMC. But the competition is > really heating up with Intel and Samsung having made several > recent announcements. We do live in interesting times :-) > -- richard > _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
