Re: auto-sizing wal_buffers

> Depends what people want to do.  We could make the default "0kB", and
> define that to mean "auto-tune", or we could remove the parameter
> altogether.  I think I was envisioning the latter, but if people are
> hesitant to do that we could do the former instead.

Unfortunately, we might still need a manual parameter for override
because of the interaction between wal_buffers and
synchronous_commit=off, since it sets the max size of the unflushed data
buffer.  Discuss?

And the "auto" setting should be -1, not 0kB.  We use -1 for "use
default" for several other GUCs.

Other than that, I think Greg's numbers are fine, and strongly support
having one less thing to tune.

--                                  -- Josh Berkus                                    PostgreSQL Experts Inc.
                        http://www.pgexperts.com