Re: Caching (was Re: choosing the right platform)

Jean-Luc Lachance <jllachan@nsd.ca> writes:
> Shouldn't there be a way to lock some tables in PG cache?

In my opinion, no.  I do not think a manual locking feature could
possibly be used effectively.  It could very easily be abused to
decrease net performance, though :-(

It does seem that a smarter buffer management algorithm would be a good
idea, but past experiments have failed to show any measurable benefit.
Perhaps those experiments were testing the wrong conditions.  I'd still
be happy to see LRU(k) or some such method put in, if someone can prove
that it actually does anything useful for us.  (As best I recall, I only
tested LRU-2 with pgbench.  Perhaps Josh's benchmarking project will
offer a wider variety of interesting scenarios.)

			regards, tom lane