Oracle Database 11g Oracle Real Application Clusters Handbook, 2nd Edition, 2nd Edition

Background Process and Cache Fusion

The following sections describe the functions performed by each background process as it relates to GCS.

LMON: Lock Monitor Process

LMON maintains GCS memory structures. It handles the abnormal termination of processes and instances. Reconfiguration of locks and resources when an instance joins or leaves the cluster are handled by LMON. Activities that occur during instance reconfigurations are tracked by it in its trace file. In versions 10g R2 and later, LMON is responsible for executing dynamic lock remastering every 10 minutes. In current versions, LMON is known as the Global Enqeueue Services monitor.

LMS: Lock Manager Server

LMS is the most active Oracle RAC background process; it can become very active, ...