Persistent connections

The BladeLogic adapter supports persistent connections to the BMC Server Automation. Persistent connections reuses an opened connection to serve multiple adapter requests rather than opening and closing a new connection for each adapter request, resulting in performance improvements for the adapter.

The BladeLogic adapter can name and cache an opened connection (NSH process), based on the Job ID of the adapter request. All requests that share a common Job ID reuse the same cached NSH session rather than opening new NSH processes. For adapter requests with different Job IDs, different connections are established and cached.

Lifespan of a cached connection

Every cached connection has a corresponding time period during which the connection can be used and reused by adapter requests having the same Job ID. After this time period elapses, the cached connection is invalid and is removed from the cache.

The lifetime of each cached connection (NSH process) depends on the <ttl> value of adapter request (every adapter request contains the <ttl> value).

If the adapter module is activated on the grid, you can use the Process timeout property of the workflow to set the <ttl> value of adapter request.

An adapter request can take different values for the <ttl> element under the following scenarios:

• Irrespective of whether the Process timeout property is set or not, if a process is executed from the Development Studio, the adapter request uses a default <<ttl> value of 15 seconds.
• If no value is set for the Process timeout property, and the adapter module is activated on the grid, the server sets a very high <ttl> value of 4611686018427387887 milliseconds for adapter requests.
• If a value is set for the Process timeout property and the adapter module is activated on the grid, the specified value is set as the <ttl> value of the adapter request.