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

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@2ndquadrant.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!

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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