Detect and terminate long-running queries#

Aiven does not terminate any customer queries even if they run indefinitely, but long-running queries can cause issues by locking resources and therefore preventing database maintenance tasks.

To identify and terminate such long-running queries, you can do it from either:

Terminate long running queries from the Aiven Console#

In the Aiven Console, you can go to the Current Queries tab for your service.

PostgreSQL® service overview tab in Aiven's console

On the Current Queries page, you can check the query duration and click Terminate to stop any long-running queries.

Detect and terminate long running queries with psql#

You can login to your service by running on the terminal psql <service_uri>. Once connected, you can call the following function on the psql shell to terminate a query manually:

SELECT pg_terminate_backend(pid);

You can learn more about the pg_terminate_backend() function from the official documentation.

You can then use the following query to monitor currently running queries:

SELECT * FROM pg_stat_activity WHERE state <> 'idle';

Client applications can use the statement_timeout session variable to voluntarily request the server to automatically cancel any query using the current connection that runs over a specified length of time. For example, the following would cancel any query that runs for more 15 seconds automatically:

SET statement_timeout = 15000

You may check the client connection defaults documentation for more information on the available session variables.

Database user error#

If you run the above command using a database user not being a member of the database you’re connecting to, you will encounter the error:

ERROR:  must be a member of the role whose process is being terminated or member of pg_signal_backend

You can check the roles assigned to each user with the following command:

SELECT r.rolname as username,r1.rolname as "role"
FROM pg_catalog.pg_roles r
    JOIN pg_catalog.pg_auth_members m
        ON (m.member = r.oid)
    JOIN pg_roles r1 ON (m.roleid=r1.oid)
WHERE r.rolcanlogin

where you would see the following:

username |        role
avnadmin | pg_read_all_stats
avnadmin | pg_stat_scan_tables
(3 rows)

To be able to check the database owner and grant the role, you can run the following:


which you should see the role:

   Name    |  Owner   |
 testdb    | testrole |

To resolve the permission issue, you may grant the user the appropriate role as per below:

grant testrole to avnadmin;