Averting Lock Contention Associated with Core-Based Hardware Threading in a Split Core Environment

A computer program product for managing lock contention, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code embodied therewith, the computer-readable program code executable by a processor to cause the processor to:

• track a current total amount of time that one or more software threads are prevented from execution due to a lock;
• track a current utilization of one or more hardware threads in the processor;
• track a current number of dispatchable software threads;
• if the current total amount of time exceeds a predetermined threshold, perform a comparison of the current total amount of time, the current utilization, and the current number of dispatchable software threads to one or more past measurements;
• based on the comparison, determine if reducing a number of active hardware threads will reduce a wait time;
• and
• if reducing the number of active hardware threads will reduce the wait time, reduce the number of active hardware threads.

A system, comprising:

• a processor;
• and
• a memory storing a program, which, when executed on the processor, performs an operation for managing lock contention, the operation comprising:
• tracking a current total amount of time that one or more software threads are prevented from execution due to a lock;
• tracking a current utilization of one or more hardware threads in the processor;
• tracking a current number of dispatchable software threads;
• if the current total amount of time exceeds a predetermined threshold, performing a comparison of the current total amount of time, the current utilization, and the current number of dispatchable software threads to one or more past measurements;
• based on the comparison, determining if reducing a number of active hardware threads will reduce a wait time;
• and
• if reducing the number of active hardware threads will reduce the wait time, reducing the number of active hardware threads.