12.03.2026 14:25, Yura Sokolov пишет: > 06.03.2026 00:01, Andres Freund пишет: >> Hi, >> >> On 2026-03-05 15:38:24 -0500, Andres Freund wrote: >>>> On Thu, 5 Mar 2026 at 21:16, Andres Freund <[email protected]> wrote: >>>>> >>>>> But it does seem like it could be a problem for incremental backup / >>>>> walsummarizer? >>>> >>>> I don't think it is, because that doesn't do calculations for non-main >>>> forks, it considers those forks always changed and includes them in >>>> full. Or at least, that was the response I got when I raised concerns >>>> about the FSM back when the incremental backup feature was being >>>> developed [0]. >>> >>> There's explicit code for ignoring the FSM, but I don't see the same for the >>> VM. And that makes sense: VM changes are mostly WAL logged, just not >>> completely / generically (i.e. this complaint), whereas FSM changes are not >>> WAL logged at all. >> >> Unfortunately I can confirm that incremental backups end up with an outdated >> VM. > > That is why pg_probackup still archive VM at whole in incremental (WAL > parsing) backup. > That is why WAL-G's incremental backup in WAL-parsing mode is (was?) > considered unstable. > > I know the problem for couple of years. Excuse me I didn't write about. > > I didn't recognize fix could be as simple as registering VM buffers. > My bad. I fill so stupid :-( Should LSN properly set as well on vm page? To maximum of concurrent updates, of course.
-- regards Yura Sokolov aka funny-falcon
