Re: select count() out of memory

 writes:

> max_connections = 1000

Do you actually have anywhere near this number of processes? What is your
setting for work_mem? Keep in mind every process could use as much as work_mem
and actually it's possible to use that much several times over.

Also, what is your maintenance_work_mem and do you have many vacuums or other
such commands running at the time?

1,000 processes is a large number of processes. You may be better off
re-architecting to run fewer processes simultaneously. But if that's not
possible you'll have to keep it in mind to tune other things properly.

-- 
  Gregory Stark
  EnterpriseDB          http://www.enterprisedb.com