Re: How to configure a read-only database server?

On 04/18/2011 06:08 PM, Stefan Keller wrote:
> * What about wal_level and archive_mode?
>

Presumably you don't care about either of these.  wal_level=minimal,
archive_mode=off.

The other non-obvious thing you should do in this situation is do all
the database maintenance in one big run after the data is loaded,
something like:

VACUUM FREEZE ANALYZE;

Otherwise you will still have some trickle of write-activity going on,
not always efficiently, despite being in read-only mode.  It's because
of what's referred to as Hint Bits:
http://wiki.postgresql.org/wiki/Hint_Bits

VACUUMing everything will clean those us, and freezing everything makes
sure there's no old transactions to concerned about that might kick off
anti-wraparound autovacuum.

The only other thing you probably want to do is set checkpoint_segments
to a big number.  Shouldn't matter normally, but when doing this freeze
operation it will help that execute quickly.  You want a lower
maintenance_work_mem on a read-only system than the master too, possibly
a higher shared_buffers as well.  It's all pretty subtle beyond the big
parameters you already identified.

--
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
"PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books