On Tue, Sep 22, 2015 at 6:01 PM, Peter Geoghegan <p...@heroku.com> wrote: > I'm doubtful that this had anything to do with MaxAllocSize. You'd > certainly need a lot of bloat to be affected by that in any way. I > wonder how high pg_stat_statements.max was set to on this system, and > how long each query text was on average.
To clarify: I think it probably starts off not having much to do with MaxAllocSize. However, it might well be the case that transient memory pressure results in the problematic code path hitting the MaxAllocSize imitation. So it starts with malloc() returning NULL, which temporarily blocks garbage collection, but in bad cases the MaxAllocSize limitation becomes a permanent barrier to performing a garbage collection (without a manual intervention). -- 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
