Michael Monnerie <michael.monnerie@xxxxxxxxxxxxxxxx> writes: > On Dienstag, 13. Februar 2007 16:34 Tom Lane wrote: >> You're suffering from a fundamental misconception about the nature of >> WAL. Vacuum doesn't "shrink WAL", and neither does anything else; > Seems you didn't understand me: When I make a vacuum, and then a base > backup, I do not need to include the WAL records anymore. But when I do > a base backup and afterwards vacuum, the WAL will be huge already, also > making restore much longer. This is irrelevant, at least in a steady-state environment. If you vacuum beforehand, the WAL history for that has to be included in what you need to recover from your previous base backup; and you can't discard that data until after you take the new backup. So AFAICS it's a wash; the average time-to-recover is the same either way. Or at least, VACUUM is not any different from any other burst of activity that you might want to schedule around. regards, tom lane
