Re: atrocious update performance

"Rosser Schwarz" <rschwarz(at)totalcardinc(dot)com> writes:
> Having never more than glanced at the output of "vacuum verbose", I
> can't say whether that makes the cut for oodles. My suspicion is no.

Nope, it sure doesn't. We occasionally see people who don't know they
need to vacuum regularly and have accumulated hundreds or thousands of
dead tuples for every live one :-(. That's clearly not the issue here.

I'm fresh out of ideas, and the fact that this is a live server kinda
limits what we can do experimentally ... but clearly, *something* is
very wrong.

Well, when you don't know what to look for, you still have to look.
One possibly useful idea is to trace the kernel calls of the backend
process while it does that ridiculously long EXPLAIN --- think you could
try that?

regards, tom lane