Oracle Enterprise Manager components are used to manage a variety of Oracle software products. In most cases, in a production environment, you will want to distribute your database and WebLogic Server instances among multiple hosts to improve performance and availability of your software resources. However, in cases where you must install multiple WebLogic Servers or databases on the same host, consider the following guidelines.
When you start Fusion Middleware Control, the Management Agent, or Database Control, Enterprise Manager immediately begins gathering important monitoring data about the host and its managed targets. Keep this in mind when you develop a process for starting the components on the host.
Specifically, consider staggering the startup process so that each Enterprise Manager process has a chance to start before the next process begins its startup procedure. Using a staggered startup procedure ensures that the processes are not in contention for resources during the CPU-intensive startup phase for each component. However, in the case of a system restart, /etc/init.d/gcstartup script which is registered during the EM deployment ensures that the OMS and the Management Agent are started automatically in a staggered manner.