PGError: server closed the connection unexpectedly

Hi,

I'm using PostgreSql database with one of my web application built in RubyOnRails, but I often fall into this error from the PostgreSql database which is installed on a VM. I'm connecting my application to a remote database. I tried to figure out the reason for this issue in various ways, but I couldn't find out why will the database give me such an error.

Error I get is.

PGError: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.

PGError: could not receive data from server: Connection timed out

I'm using the latest version of open source PostgreSql database i.e 9.2, and I get these errors very frequently which is reducing the performance of my application. Can someone help me to understand why this error occurs and how do I avoid them?

I have tried all the possible solutions available for me at my application end, which includes setting various database configuration values like timeout, pool and using latest database adaptor gems. Still couldn't find out the source of this issue nor the solution.

What does the Postgres logfile say?

I did check these two log files

/var/lib/pgsql/9.2/data/pg_log/postgresql-Wed.log
/var/lib/pgsql/9.2/data/pg_log/postgresql-Tue.log

and I find this

LOG: could not receive data from client: Connection timed out

Can you please tell me which log file I have to check. The VM where the database is installed is a CentOS release 6.3 (Final) and I have installed the PostgreSql using yum installation.

Sounds like a connection/network problem between the client (your computer) and the CentOS VM.

I did check if it was a connection problem with the network engineer where my application and database VM exists and that is not the problem. We had kept the VMs network under monitoring for a long time and didn't find any networking issues. I also made sure that the database VM and the application VM are on the same network.

Is this something to do with the PostgreSql version or any configuration settings in the PostgreSql database? I did try all the versions of PostgreSql starting from 8.1 to 9.2.

I would like to add up that the connection between database VM and application persists even with heavy loads on the database, and this PgError occurs occasionally which we couldn't determine.