On Tue, 10 Feb 2004, Tom Lane wrote: > "scott.marlowe" <[EMAIL PROTECTED]> writes: > >> 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? > > Transaction size would make no difference AFAICS. Reducing the interval > between checkpoints might make things safer in such a case. > > > 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. > > Did you try pulling the plug immediately after a CHECKPOINT command > completes? You could test by manually issuing a CHECKPOINT while > pgbench runs, and yanking power as soon as the prompt comes back.
I will try that. Thanks for the tip. I'll let you know how it works out. ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])