On Mon, 2024-07-22 at 09:37 -0400, Robert Haas wrote: > How about something like this: > > An incremental backup is only possible if replay would begin from a > later checkpoint than for the previous backup upon which it depends. > On the primary, this condition is always satisfied, because each > backup triggers a new checkpoint. On a standby, replay begins from the > most recent restartpoint. As a result, an incremental backup may fail > on a standby if there has been very little activity since the previous > backup. Attempting to take an incremental backup that is lagging > behind the primary (or some other standby) using a prior backup taken > at a later WAL position may fail for the same reason.
Before I write a v2, a small question for clarification: I believe I remember that during my experiments, I ran CHECKPOINT on the standby server between the first backup and the incremental backup, and that was not enough to make it work. I had to run a CHECKPOINT on the primary server. Does CHECKPOINT on the standby not trigger a restartpoint, or do I simply misremember? Yours, Laurenz Albe
