Arval SQLException: FATAL: sorry, too many clients already in postgres

Question

I am using a database in PostgreSQL 9.1,in which entry are coming continuously from another program . I am sending request from Ajax after 6 sec to fetch the latest entry.to

Answer 1

To increase the connection limit you may like the following document.

This solution is tested on ubuntu 12.04.

1. Make following changes in postgresql.conf file :

Open /etc/postgresql/9.1/main/postgresql.conf

max_connections = 200
shared_buffers = 100MB
max_files_per_process = 100

Reference: shared_buffers size should be less than shmmax size.

2. Commands to check shmmax:

$ sysctl -e kernel.shmmax
$ ipcs -l

Reference: Adjusting shmmax and shmall

3. Increase the size of shmmax:

Run the following command:

$ sysctl -w kernel.shmmax=134217728
$ sysctl -w kernel.shmall=2097152

and write on top in /etc/sysctl.conf file:

kernel.shmmax=134217728
kernel.shmall=2097152

Reference : SHMMAX in Ubuntu

4. Restart postgresql

$ service postgresql restart

Links:

http://www.varlena.com/GeneralBits/Tidbits/perf.html

http://www.postgresql.org/docs/9.1/static/runtime-config-resource.html

Answer 2

You can increase the max_connections in postgres, that is not the solution though. You have resource leaks. It could be any - connection not closed, result set not closed. Please go back and check the code.

Consider using a connection pooling library like c3p0/BoneCp

A general discussion on connection pooling is here (Thanks to @sinisa229 mihajlovski)