sp_sysmon reports on the following activities for cluster locks:
Lock Garbage Collection – number of times lock garbage collection ran. A large number of garbage collections per second indicates the cluster has an insufficient number of locks.
Targeted Collection Success – number of times lock garbage collection was able to successfully reclaim the targeted number of locks. The Cluster Edition determines the target number for locks internally, and is not a configurable parameter. A low number of garbage collections per second indicates the cluster has an insufficient number of locks or insufficient amount of CIPC message space available.
Cluster Lock Requests – number of user physical, logical, or object lock requests that cannot be granted because of retention and require cluster communication. A high value indicates a lot of cluster traffic.
Local Master – number of physical, logical, or object locks that have a local master. A higher value indicates ideal lock, possibly indicating smaller overhead while serving cluster lock requests.
If the Cluster Edition cannot find the local master:
You may need to reassess your application partitioning.
A single instance has too great a load, which is leading to load balancing of master to remote instance. Consider changing your workload pattern and schema (such as partitioning your data).
Lock Granted – number of cluster lock requests
that wait for a remote instance that owns the cluster lock with
no conflicting task ownership. A high value for Lock
Granted
indicates conflicting lock requests
from multiple instances in cluster. Reassess your application partitioning.
Lock Waited – number of cluster lock requests
that wait for a remote instance that owns the cluster lock with
conflicting task ownership. A high value for Lock
Waited
indicates lock level contention: two
tasks on different instances are attempting to acquire the same
lock and are in conflict. To rectify, reassess your application
partitioning.
Downgrade Req Recv – displays the number of downgrade requests sent by a remote instance when it asks for a lock that is owned by the local instance.