SSL On Large Grids

The Apache Tomcat AJP Connector can support many keep-alives (KA); however, the KA timeout is set to a default value of 60 seconds to reduce load on the Manager. This means that any time a new connection is necessary, the client must perform an SSL handshake to establish the HTTPS connections, which can impact performance.

Drivers poll on a regular basis, so they can maintain their connections. However, Engines can lose their connections when working on long tasks if the heartbeat is longer than the KA timeout. Idle Engines also lose connections on large grids where the Engine Wait time is longer than the KA timeout.

If you require HTTPS for Engines and you have a large grid with many Engines, you might notice Broker performance issues. Consider increasing this timeout to alleviate this issue. However, you must also monitor Broker performance, as this increases the number of connections that the AJP connector must poll.

Keep-alive is configured in Engine Configurations, located in the Administration Tool at Grid Components > Engines > Engine Configurations. The property to change is File Server > Keep Alive Time (seconds).