On Fri, Jun 17, 2011 at 3:08 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
> Not so. The extra locking would only occur on the first lock
> acquisition after DDL operations occur. If that was common then your
> other performance patch would not be an effective optimisation. There
> is no additional locking from what I've proposed in the common code
> path - that's why we have a relcache.
The extra locking would also occur when *initially* building relcache
entries. In other words, this would increase - likely quite
significantly - the overhead of backend startup. It's not going to be
sufficient to do this just for pg_class; I think you'll have to do it
for pg_attribute, pg_attrdef, pg_constraint, pg_index, pg_trigger,
pg_rewrite, and maybe a few others I'm not thinking of right now.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
