“Log Semaphore Contention” reports the number of times a task was switched out because it needed to acquire the transaction log semaphore held by another task. This applies to SMP systems only.
If log semaphore contention is high, see “Transaction management”.
Check disk queuing on the disk used by the transaction log.
Also see “Engine busy utilization”. If engine utilization reports a low value, and response time is within acceptable limits, consider reducing the number of engines. Running with fewer engines reduces contention by decreasing the number of tasks trying to access the log simultaneously.