On Fri, Apr 5, 2019 at 9:56 AM Michael Paquier <mich...@paquier.xyz> wrote:
> On Fri, Apr 05, 2019 at 09:41:58AM +0200, Michael Banck wrote: > > Is there a good reason why Postgres doesn't just issue a CHECKPOINT > > after promote itself? After all, this seems to be about making the > > control file having the proper content, which sounds like a good thing > > to have in general. > > The startup process requests a checkpoint since 9.3, and before that > it was doing the checkpoint by itself (grep for fast_promoted and > RequestCheckpoint() around line 7579 in xlog.c). This allows the > recovery to finish much faster. > > > Could this be a problem for anything else besides pg_rewind? > > Not that I know of, at least not in the tree. > > > This looks like a needless footgun waiting to happen, and just > > documenting it in pg_rewind's notes section looks a bit too hidden to me > > (but is certainly an improvement). > > We had a couple of reports on the matter over the past years. Perhaps > we could use a big fat warning but that feels a bit overdoing it. > A related question is, could we (for 12+) actually make the problem go away? As in, can we detect the state and just have pg_rewind issue the checkpoint as needed? -- Magnus Hagander Me: https://www.hagander.net/ <http://www.hagander.net/> Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>
