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How Resources Work

The Manage Resources operator is in the Process Control operator group. A process can use the Manage Resources operator to take available units from a specified resource. If all units of the specified resource are taken (in the same or different processes), the Manage Resources operator delays processing along that branch until the resource has free units.

The following design shows a process taking one unit from the process quota resource before running an application. If there are available units in the process quota resource, processing continues to Run Application 1. If there are no available resource units, processing does not start until either units become available or the operator times out. After the Run Application 1 operator ends, the resource unit is freed back to the process quota resource, and processing continues with subsequent operators in the process.

Resources let you define the number of units available and how many units are consumed. A resource consists of a maximum number of units, the current value of available units, and a flag indicating whether the resource is locked.

You can take the following actions with resources:

• Take a specified quantity of units of an available resource. Enter a higher value in the Used field.
• Free a specified quantity of units of an available resource. Enter a lower value in the Used field.
• Lock a resource
• Unlock a resource

A Manage Resources operator can consume or free any specified number of resources. As a developer or administrator, you can use Manage Resources operators to tune the load balancing on a particular touchpoint. You can also lock a resource to prevent consumption of resource units by any other process.

The following constraints apply to resources:

• The maximum number of units of any resource is an arbitrary value that you can calibrate and fine-tune for your system requirements. The number of resources that a process uses is also arbitrary. The maximum limit is 9,999; however, let performance and architecture be your guide. Allocate resource units to processes to best suit your implementation requirements.
• The currently used value of resource units is always less than or equal to the maximum value of the resource.
• A resource-dependent process must wait until its specified number of units is available.
• Operators cannot consume units from a locked resource.
• Operators cannot lock a resource that another process has locked.