On Fri, Sep 16, 2011 at 6:51 AM, Liyun Yu <liyu...@med.unc.edu> wrote: > Anyone used the OWC (other world computing) SSD (6G) for RAID Array? > Any suggestions/recommendations on SSD based RAID on the market > or drives good for RAID ?
OWC's SSDs are SandForce-based. OCZ (not OWC) is probably the biggest SandForce-based SSD manufacturer. > I did not access the SSD market for a while. Yesterday one of our colleagues > sent me a link at OWC which indicated that their drives has writing speed > above 500MB SandForce uses compression and de-duplication. That 500MB/s number is not really 500MB/s because with compression and de-duplication it doesn't actually have to right all that data. When tested with random uncompressible data SandForce drives perform about the same as Intel drives. SSDs are great for random reads and writes, like database servers, they aren't really worth it for sequential writes. > Tom's hardware site which was more than 8 months old. AnandTech has the best consumer SSD articles: http://www.anandtech.com/tag/storage On Fri, Sep 16, 2011 at 11:07 AM, <da...@lang.hm> wrote: > one thing to watch out for with SSDs, most of them do not have good behavior > in the face of power failures. The Intel G1 and G2 drives lost data on power failure. The G3s (SSD 320) have a supercap and they do not lose data. There was a firmware bug the killed the drives on power failure, referred to as the "Addresses Bad Context 13x Error", that was fixed in August. The SandForce drives without super capacitors or discrete capacitors lose data on power failure. SMART Modular makes some SandForce drives with capacitors. On Fri, Sep 16, 2011 at 12:08 PM, Luke S. Crawford <l...@prgmr.com> wrote: > I've heard this as well... but in my experience, SSDs fail like disks, > not like tires, which is to say, the failure pattern seems fairly random, > and more correlated to age than to use. In my experience consumer SSDs (e.g., Intel and SandForce) fail at a much higher rate than enterprise HDDs. Purely anecdotal evidence here, not a scientific study. Given 100 servers with 8 SSDs each and 100 servers with 8 15k SAS disks each, the difference in failure rate is extreme. For the first 3 years the SAS HDDs would fail at a rate of 1 every 6 months. After 3 years, maybe 1 every 2 months. Throughout the life of the SSDs they would fail at a rate of 1 a week, sometimes the failures clustered, often leading to multiple failures a week. The most common failure was sectors becoming unreadable or unwritable. The firmware didn't seem to correct the bad sectors. Sometimes the firmware would completely fail, and the drive would be lost. Overall the firmware of consumer SSDs does not seem to be as mature as enterprise spinning disks, leading to odd failure scenarios. To sum it up, I'd trust consumer SSDs in my laptop, I'd trust them for L2ARC, I wouldn't trust them as primary storage for critical data like an Oracle database. -Anton _______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
