After reading the comments last week about SSDs, I did some testing of the ones we have at work - each of my test-boxes (three with SSDs, one with HDD) subjected to multiple stand-alone plug-pull tests, using pgbench to provide load. So far, there've been no instances of PostgreSQL data corruption, but diskchecker.pl reported huge numbers of errors. What exactly does this mean? Is Postgres doing something that diskchecker isn't, and is thus safe? Could data corruption occur but I've just never pulled the power out at the precise microsecond when it would cause problems? Or is it that we would lose entire transactions, but never experience corruption that the postmaster can't repair? Interestingly, disabling write-caching with 'hdparm -W 0 /dev/sda' (as per the llivejournal blog[1]) reduced the SSD's error rates without eliminating failures entirely, while on the HDD, there were no problems at all with write caching off. ChrisA -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
