By default, an IIS application pool (or “AppPool”) recycles on a regular time interval of 1740 minutes or 29 hours.
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Open IIS MANAGER (command: inetmgr)
Go to Application Pool section
right-click TFS4JIRA application pool (default name: TFS4JIRA Sync App Pool)
choose ADVANCED SETTINGS
please set: Start Mode to AlwaysRunning
please set: Idle Time-out (minutes) to 0
click OK to confirm changes
Expand Sites and Default Web SIte (please note: this is default TFS4JIRA installation site, you may have a different configuration)
Right-click TFS4JIRA application (default name: tfs-jira-synchronizer)
go to MANAGE APPLICATION → ADVANCED SETTINGS
please set: Preload Enabled to True
As a final step please restart your site (site where TFS4JIRA application is installed)
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Please of course remember to enter your synchronizer address and port.
DISABLE APPLICATION POOL AUTOMATIC RECICLING
Open IIS MANAGER (command: inetmgr)
Go to Application Pool section
Right-click TFS4JIRA application pool
Choose Recycling …
Clear any fixed intervals setup