is restart necessary after a config change in mongodb?

Question

After a configuration change is it necessary to restart the db so that the new config take effect?

The configuration was changed via this command:

db.getSiblingDB('admin').runCommand( { setParameter: 1, cursorTimeoutMillis: 300000000 } )

Answer 1

As per Jira ticket and MongoDB documentation, it does not mention of requiring a restart.

ISSUE SUMMARY

Client cursors that are no longer used may not be closed by the server. These cursors continue to consume resources inside mongod. By default, inactive cursors expire after 10 minutes, this option makes it possible to configure this timeout.

RESOLUTION DETAILS

By specifing the cursorTimeoutMillis option, administrators can configure mongod or mongos to automatically remove idle client cursors after a specified interval. The timeout applies to all cursors maintained on a mongod or mongos, may be specified when starting the mongod or mongos and may be modified at any time using the setParameter command. Consider the following examples.

cursorTimeoutMillis

New in version 3.0.2.

Default: 600000 (i.e. 10 minutes)

Available for both mongod and mongos.

Sets the expiration threshold in milliseconds for idle cursors before MongoDB removes them; i.e. MongoDB removes cursors that have been idle for the specified cursorTimeoutMillis.

For example, the following sets the cursorTimeoutMillis to 300000 milliseconds (i.e. 5 minutes).

But some users saw the value did not take effect till restart.

https://groups.google.com/forum/#!msg/mongodb-user/_nYxRY0iDr0/HeRpqRIIBwAJ