On Sun, May 4, 2014 at 6:49 AM, Andres Freund <and...@2ndquadrant.com> wrote: > + <listitem> > + <para> > + Have pg_stat_statements use a flat file for query text storage, > allowing higher limits (Peter Geoghegan) > + </para> > + > + <para> > + Also add the ability to retrieve all pg_stat_statements information > except the query text. This allows programs to reuse the query > + text already retrieved by referencing queryid. > + </para> > + </listitem> > > This isn't an optional thing, is it?
This is intended to be used by time-series monitoring tools that aggregate and graph pg_stat_statements data temporally. They usually won't need query texts, and so can only retrieve them lazily. The pg_stat_statements view presents exactly the same interface for ad-hoc querying, though. The point of the first item is that there is no longer *any* limitation on the size of stored query texts. They are no longer truncated to track_activity_query_size bytes. The shared memory overhead is also decreased substantially, allowing us to increase the default pg_stat_statements.max setting from 1,000 to 5,000, while still reducing the overall shared memory overhead (assuming a default track_activity_query_size). I think that the removal of the limitation, and the substantial lowering of the per-entry footprint should both be explicitly noted. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
