Server Mode and the ALPool

The process of creating a clone AssemblyLine can be optimized by using the AssemblyLine Pool (ALPool). On event detection, the Server mode Connector either proceeds with the Flow section of this AL; or if an ALPool is configured for this AL, then it contacts the Pool Manager process to request an available AssemblyLine instance to handle this event.

When an AssemblyLine with a Server mode Connector uses the ALPool, the ALPool will execute AssemblyLine instances from beginning to end. Before the AssemblyLine instance in the ALPool closes the Flow Connectors, the ALPool retrieves those Connectors into a pooled connector set that will be reused in the next AssemblyLine instance created by the ALPool. In essence, the ALPool uses the tcb.setRuntimeConnector() method.

There are two system properties that govern the behavior of Connector pooling:

com.ibm.di.server.connectorpooltimeout

This property defines the timeout in seconds before a pooled connector set is released.

Table 1. Connector Pool Timeout property Value table

Value	Significance
< 0	Disable Connector pooling
0	Timeout disabled; pool Connectors never timeout
> 0	Number of seconds before pooled Connectors timeout

com.ibm.di.server.connectorpoolexclude

This property defines the Connector types that are excluded from pooling. If a Connector's class name appears in this comma separated list it is not included in the Connector pool set.

Connectors are never shared. They are only assigned to a single AssemblyLine instance when used.

Parent topic: Server mode