Re: Moving postgresql.conf tunables into 2003...

Josh Berkus <josh@agliodbs.com> writes:
> Tom Comments:
>> I was arguing awhile back for bumping the default shared_buffers up,
>> but the discussion trailed off with no real resolution.

> I think we ran up against the still far-too-low SHMMAX settings in most
> *nixes.   We could raise this default once we can supply a script which will
> help the user bump up the OS's memory settings at, say, initDB time.

Actually, I think it would not be hard to get initdb to test whether
larger shared-memory settings would work.  We could do something like
try -B of 64, 256, 512, 1024, and insert into postgresql.conf the
largest value that works.  I would want it to top out at a few thousand
at most, because I don't think a default installation should try to
commandeer the whole machine, but if we could get the typical
installation to be running with even 1000 buffers rather than 64,
we'd be *way* better off.  (See "Postgres vs MySQL" thread nearby.)

We could possibly also have initdb print some kind of message if it's
forced to use an unreasonably small value for shared_buffers, so that
people might have a clue that they need to do kernel reconfiguration.

Comments?

            regards, tom lane