---- Original message ---- >Date: Wed, 24 Aug 2011 21:32:16 +0200 >From: pgsql-performance-owner@xxxxxxxxxxxxxx (on behalf of "Tomas Vondra" <tv@xxxxxxxx>) >Subject: Re: Reports from SSD purgatory >To: gnuoytr@xxxxxxx >Cc: pgsql-performance@xxxxxxxxxxxxxx > >On 24 Srpen 2011, 20:48, gnuoytr@xxxxxxx wrote: > >> It's worth knowing exactly what that means. Turns out that NAND quality >> is price specific. There's gooduns and baduns. Is this a failure in the >> controller(s) or the NAND? > >Why is that important? It's simply a failure of electronics and it has >nothing to do with the wear limits. It simply fails without prior warning >from the SMART. It matters because if it's the controller, there's nothing one can do about it (the vendor). If it's the NAND, then the vendor/customer can get drives with gooduns rather than baduns. Not necessarily a quick fix, but knowing the quality of the NAND in the SSD you're planning to buy matters. > >> Also, given that PG is *nix centric and support for TRIM is win centric, >> having that makes a big difference in performance. > >Windows specific? What do you mean? TRIM is a low-level way to tell the >drive 'this block is empty and may be used for something else' - it's just >another command sent to the drive. It has to be supported by the >filesystem, though (e.g. ext4/btrfs support it). My point. The firmware and MS have been faster to support TRIM than *nix, linux in particular. Those that won't/can't move to a recent kernel don't get TRIM. > >Tomas > > >-- >Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) >To make changes to your subscription: >http://www.postgresql.org/mailpref/pgsql-performance -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
