[Pgbouncer-general] "closing because: client unexpected eof" error in pgbouncer

[Anshu Avinash]

Hi

I've set up pgbouncer in transaction pool mode with default_pool_size as
20. I'm connecting to pgbouncer from my rake tasks and occasionally see
this error in pgbouncer log:
"closing because: client unexpected eof (age=3110)"

Corresponding error on the client side:

ActiveRecord::StatementInvalid: PG::ConnectionBad: PQconsumeInput() could
not receive data from server: Connection timed out

Also this errors don't happen if I directly connect to postgres. Using
transaction pooling in pgbouncer and rails has created problems for people
in past. I followed this blog post:
https://gocardless.com/blog/the-troubleshooting-tales-issues-scaling-postgres-connections/
and upgraded my rails version to 4.2.5, but that doesn't fix this error.

Is this an issue at the client side or a config issue in pgbouncer?
Attaching my pgbouncer config file.

I have also asked this on stackoverflow:
http://stackoverflow.com/q/38294359/1843751
Any help in debugging this issue would be appreciated!

[Greg Sabino Mullane]

Post by Anshu Avinash
"closing because: client unexpected eof (age=3110)"

This means the client sent something unexpected to pgbouncer.

Post by Anshu Avinash
ActiveRecord::StatementInvalid: PG::ConnectionBad: PQconsumeInput() could
not receive data from server: Connection timed out

PQconsumeInput is a pretty good indication that you are trying to use
(perhaps indirectly) LISTEN/NOTIFY, which is not allow in pgbouncer's
transaction mode. To use LISTEN/NOTIFY, you need to drop back to session
mode.