Re: what does pg_activity mean when the database is stuck?

I have a problem where postgresql 9.3 got stuck, and the number of postgresql processes increased from about 15 to 225 in 10 minutes.

I ran the query:

select pid, query_start, waiting, state, query from pg_stat_activity order by query_start;

But it showed mostly select statements -- all of them the same one, with a couple of joins.  They are not in a waiting state but have been running for over 2 hours.  

I also checked for locks with the query on

http://wiki.postgresql.org/wiki/Lock_Monitoring

But it returned no locked tables.

So what does this mean?  Is the select query getting stuck?