Arbortext Publishing Engine Programmer's Guide (Guide de programmeur d'Arbortext Publishing Engine) > The Arbortext Publishing Engine Request Manager > Understanding the Internal Structure of Arbortext PE Request Manager > Sous-processus Arbortext PE Pool Management > Sous-processus Arbortext PE Pool Work Thread
  
Sous-processus Arbortext PE Pool Work Thread
Each Sous-processus Arbortext PE pool starts a background work thread that runs periodically and attempts to perform routine maintenance. The interval between runs is configured in the workThreadInterval attribute of each SubprocessPool element in e3config.xml. The default is every 5 seconds. Each time it runs, a work thread checks for the following items. Descriptions of each item follows.
unusable Sous-processus Arbortext PE
Sous-processus Arbortext PE that should be terminated
Sous-processus Arbortext PE that have exceeded the allowed idle or lifetime period
deferred requests to delete directories
whether a new Sous-processus Arbortext PE should be started