Lock monitoring in a Db2 pureScale environment overview

In a Db2 pureScale environment, the fact that different members work with the same data introduces the possibility of another type of contention for data: when two members want to update the same object. When a member needs a lock for an object, the local lock manager (LLM) component within the member works with the global lock manager (GLM): if the LLM does not already hold a lock for the object in question, the LLM requests a lock from the GLM. In this way, the GLM mediates requests for locks from different members.

When viewed at the global level for the Db2 pureScale instance, monitor elements such as locks_held, or lock_wait_time report data on all locks in the instance, both within and between members. Monitor elements added specifically for the Db2 pureScale Feature can be used to examine just the lock waits between members.