On Wed, Mar 4, 2020 at 6:15 AM Michael Paquier <mich...@paquier.xyz> wrote: > > On Tue, Mar 03, 2020 at 06:25:51PM +0900, Michael Paquier wrote: > > Or actually, a more simple solution is to abuse of the two existing > > routines so as the dependency switch is done the other way around, > > from the new index to the old one. That would visibly work because > > there is no CCI between each scan, and that's faster because the scan > > of pg_depend is done only on the entries in need of an update. I'll > > look at that again tomorrow, it is late here and I may be missing > > something obvious. > > It was a good inspiration. I have been torturing this patch today and > played with it by injecting elog(ERROR) calls in the middle of reindex > concurrently for all the phases, and checked manually the handling of > entries in pg_depend for the new and old indexes, and these correctly > map. So this is taking care of your problem. Attached is an updated > patch with an updated comment about the dependency of this code with > CCIs. I'd like to go fix this issue first.
Thanks for the patch! I started to look at it during the weekend, but I got interrupted and unfortunately didn't had time to look at it since. The fix looks good to me. I also tried multiple failure scenario and it's unsurprisingly working just fine. Should we add some regression tests for that? I guess most of it could be borrowed from the patch to fix the toast index issue I sent last week.
