[pgpool-general: 3514] Re: pgpool 3.3.4 not responding to new SQL connections

Tatsuo Ishii ishii at postgresql.org
Mon Mar 16 13:56:39 JST 2015

I suspect you run out num_init_children and there's no free pgpool-II
process to accept new connection. To make sure that you could use ps
command. For pgpool-II to accept new connections from clients, there
must be process which looks like something like this:

17167 pts/2    S      0:00 pgpool: wait for connection request                                                             

Best regards,
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php

> Hi!
> I've been using 3.3.4 in a new deployment and from time to time pgpool
> doesn't reply anything to new PSQL connections.
> Either with PgAdmin or a JDBC app or PSQL command line, the initial
> handshake stays frozen. However we can connect to the Psql backends
> directly throught their local ports.
> I've got pgpool  right now with *replication mode = on* (but only 1 active
> node) and *'connection_cache = on'* with default values for pooling.
> I cannot guess what's the SQL query that is hanging pgpool process. Is
> pgpool waiting for some some reply from PSQL? If it is so, why does it
> block all other connections?
> Machine resources are OK (5% cpu and 10% RAM used)
> After 20-30min (not sure) Pgpool accepts again new PSQL connections.
> I am looking right now at pgpool's log with debug level = 1, but it is a
> bit hard to understand the errors kind: T, C, etc... and so many lines per
> second.
>  I'll keep  looking though.
> Thanks.

More information about the pgpool-general mailing list