On Mon, 9 Feb 2004, Tom Lane wrote: > "scott.marlowe" <[EMAIL PROTECTED]> writes: > > That said we have a really HUGE (~200 drive) IDE storage array my web / > > app server sits on top of. No clue if that thing will reliably work under > > a database, and I'm in no hurry to find out. > > > But since the fsync on WAL is all that seems important, I could always > > initlocation a big chunk of it and keep the WAL local and I should be ok. > > Unfortunately not --- at checkpoint time, the constraint goes the other > way. We have to be sure all the data file updates are down to disk > before we write a checkpoint record to the WAL log. So you can still > get screwed if the data-file drive lies about write completion.
Hmmm. OK. Would the transaction size be an issue here? I.e. would small transactions likely be safer against corruption than large transactions? I ask because most of the testing I did was with pgbench running 100+ simos (on a -s 100 pgbench database) and as long as the WAL drive was fsyncing correctly, the database survived. ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
