siebmtshmw.exe

We ran into a problem running out of memory and the siebel server was not responding. Taking a closer look at the logs and the processes running, there were lot siebmtshmw.exe's running in the task manager.

This was because after the installation, we had not disabled any of the components which were active by default.

Note from Metalink was helpful in resolving the issues

All the components which are enabled are by default started when the server is started. Users will need to identify the components to enable and disable the components which are not needed, so that they are not started when the server is started. Each siebmtshmw.exe shell consumes about 30-40 MB without catering to any tasks/requests. To disable components log into srvrmgr
Srvrmgr : siebsrvrname > disable comp

To identify which component is related to which OS process, the Siebel administrator can refer to the enterprise log (..log) file under /log directory on windows and /enterprises//log directory on Unix

An example of the enterprise log file content which shows the OS pid:

ServerLog ProcessCreate ...... Created multithreaded server process (OS pid = 2052) for Call Center Object Manager with task id 21508

After disabling the unnecessary active object managers and processes like ADM, Assignment Manager, the server started responding.