Andres Freund <and...@anarazel.de> writes: > On 2019-04-16 14:31:25 -0400, Tom Lane wrote: >> This can only work at all if an inaccurate map is very fail-soft, >> which I'm not convinced it is
> I think it better needs to be fail-soft independent of this the no-fsm > patch. Because the fsm is not WAL logged etc, it's pretty easy to get a > pretty corrupted version. And we better deal with that. Yes, FSM has to be fail-soft from a *correctness* viewpoint; but it's not fail-soft from a *performance* viewpoint. It can take awhile for us to self-heal a busted map. And this fake map spends almost all its time busted and in need of (expensive) corrections. I think this may actually be the same performance complaint you're making, in different words. regards, tom lane