Reducing contention of transaction logging in a database management system

摘要

System, method, computer program product embodiments and combinations and sub-combinations thereof for reducing contention of transaction logging in a database management system (DBMS) are provided. An embodiment includes creating a dependency relationship among private log caches (PLCs) having individual associations with tasks in a DBMS. The dependency relationship is utilized to control buffer pinning and unpinning among the PLCs without involving a flushing of the PLCs during transactions of the tasks.

主权项

1. A method for reducing contention of transaction logging in a database management system (DBMS) having a memory and a processor coupled to the memory, the method comprising:
creating a dependency relationship among private log caches (PLCs) having individual associations with tasks in the DBMS, wherein the PLCs store log records of the tasks before the log records are posted in the DBMS and,
wherein creating the dependency relationship further comprises using synchronization markers as flush points that synchronize an order for flushing the log records stored in the PLCs, and wherein a synchronization marker has a PLC indicator and a memory offset such that the PLC indicator indicates a PLC of the PLCs unassociated with the task and the memory offset indicates a memory location in the PLC unassociated with the task up to which the log records require flushing; and controlling, using the synchronization markers, buffer pinning and unpinning among the PLCs without involving a flushing of the PLCs during transactions of the tasks, wherein the controlling buffer pinning and unpinning comprises annotating the PLC of the PLCs associated with the task with the synchronization marker as a flush point that synchronizes an order for flushing log records in the PLC associated with the task and the log records of the PLC unassociated with the task, at the time the log records are being flushed, and wherein the PLCs are stored in the memory and the pinning and unpinning among the PLCs uses the processor.