Scalable thread locking with customizable spinning

摘要

Embodiments described herein are directed to dynamically controlling the number of spins for a selected processing thread among a plurality of processing threads. A computer system tracks both the number of waiting processing threads and each thread's turn, wherein a selected thread's turn comprises the total number of waiting processing threads after the selected thread's arrival at the processor. Next, the computer system determines, based on the selected thread's turn, the number of spins that are to occur before the selected thread checks for an available thread lock. The computer system also, based on the selected thread's turn, changes the number of spins, such that the number of spins for the selected thread is a function of the number of waiting processing threads and processors in the computer system.

主权项

1. A computer program product comprising the following:
one or more computer-readable hardware storage devices having stored thereon computer-executable instructions that, when executed by one or more processors of the computing system, cause the computing system to perform a methodfor implementing a customized spin for a selected processing thread based on the thread's turn, the method comprising:
an act of initializing a single integer variable configured to keep track of the following: the status of a lock bit indicating whether a lock has been acquired or not, a number of waiting threads, and the status of a thread tracking flag;an act of checking the lock bit to determine whether the lock is available for a the selected processing thread;upon determining that the lock is available, an act of assigning the lock to the selected processing thread; andupon determining that the lock is unavailable, an act of one of said number of waiting threads incrementing the selected thread's waiting count by two.