Spawn Threshold

Enter a parameter that's supplied to Tuxedo for control of process spawning by using the -p command-line option for all server processes. The default setting (1,600:1,1) rarely needs to be changed.

This setting enables the dynamic decay of spawned server processes as the transaction volume decreases. The value can be loosely translated to mean that if, in 600 seconds, there is less than or equal to one job in the queue, the decay process begins. This is described in more detail in the timeout settings topic of this product documentation.

New server processes will be spawned according to the rule defined here. By default, if there is one outstanding request in the queue for one second or more, an additional process is spawned. Additional processes will be spawned all the way up to the Max Instances defined for that server type. If Max Instances and Min Instances are identical, this setting has no effect.

Note:

This parameter applies only if, for PSAPPSRV, the value of Max Instances is greater than that of Min Instances. By default, spawning is disabled.

For more information, also see servopts(s) in the Oracle Tuxedo reference manual.

Spawning results in resource-intensive demands at process initialization because it takes place mainly when the system is starting to undergo increased load and increased queues. In this scenario, you may want to manually scale the size of a domain by starting additional domain processes as desired. In order to manually scale the size of a domain, you need to disable spawning by not entering a value for the Spawn Threshold configuration parameter, which disables the dynamic process spawning for the domain. As a result, you can set the minimum and maximum instances of PSAPPSRV to different values, and you can manually start additional domain processes as desired.