ActiveYarns is a read-only TIdThreadSafeList property that represents the thread-based or the fiber-based tasks allocated by the scheduler. ActiveYarns is instantiated during initialization of the component. 

ActiveYarns is used in methods that create, manage, or free the TIdYarn instances like AcquireYarn, ReleaseYarn, TerminateAllYarns. 

ActiveYarns is freed in the Destroy destructor. 

Use AcquireYarn to get the thread or fiber for the client connection task. 

Use StartYarn to begin executing a thread or fiber for the client connection task. 

Use TerminateYarn to stop executing the thread or fiber for the client connection task. 

Use TerminateAllYarns to force termination of all TIdYarn instances in ActiveYarns. 

Use ReleaseYarn to free a yarn in ActiveYarns that has already been terminated.

TIdThreadSafeList 

TIdYarn 

AcquireYarn 

StartYarn 

TerminateYarn 

TerminateAllYarns 

ReleaseYarn