Re: Plug-pull testing worked, diskchecker.pl failed

On Wed, Nov 7, 2012 at 01:53:47PM -0700, Scott Marlowe wrote:
> On Wed, Nov 7, 2012 at 11:59 AM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > On Sat, Oct 27, 2012 at 05:41:02PM +1100, Chris Angelico wrote:
> >> On Sat, Oct 27, 2012 at 4:26 PM, Greg Smith <greg(at)2ndquadrant(dot)com> wrote:
> >> > In general, through, diskchecker.pl is the more sensitive test. If it
> >> > fails, storage is unreliable for PostgreSQL, period. It's good that you've
> >> > followed up by confirming the real database corruption implied by that is
> >> > also visible. In general, though, that's not needed. Diskchecker says the
> >> > drive is bad, you're done--don't put a database on it. Doing the database
> >> > level tests is more for finding false positives: where diskchecker says the
> >> > drive is OK, but perhaps there is a filesystem problem that makes it
> >> > unreliable, one that it doesn't test for.
> >>
> >> Thanks. That's the conclusion we were coming to too, though all I've
> >> seen is lost transactions and not any other form of damage.
> >>
> >> > What SSD are you using? The Intel 320 and 710 series models are the only
> >> > SATA-connected drives still on the market I know of that pass a serious
> >> > test. The other good models are direct PCI-E storage units, like the
> >> > FusionIO drives.
> >>
> >> I don't have the specs to hand, but one of them is a Kingston drive.
> >> Our local supplier is out of 320 series drives, so we were looking for
> >> others; will check out the 710s. It's crazy that so few drives can
> >> actually be trusted.
> >
> > Yes. Welcome to our craziness!
>
> Is there a comprehensive list of drives that have been tested on the
> wiki somewhere? Our current choices seem to be the Intel 3xx series
> which STILL suffer from the "whoops I'm now an 8MB drive" bug and the
> very expensive SLC 7xx series Intel drives, the Hitachi Ultrastar
> SSD400M, and the OCZ Vertex 2 Pro. Any particular recommendations
> from those or other series from anyone would be greatly appreciated.

No, I know of no official list. Greg Smith and I have tried to document
some of this on the wiki:

http://wiki.postgresql.org/wiki/Reliable_Writes

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +