You may get this kind of error in the Web Agent log:
[14/Apr/2011:14:47:06] [Error] [CA WebAgent IPC] [CSmSharedSegment::smalloc] Error allocating shared memory segment using key 0x6cc7b0a7 - File exists (17)
[14/Apr/2011:14:47:06] [Info] [CA WebAgent IPC]  [CSmSem::SemRm] Removed semaphore 45285378
[14/Apr/2011:14:47:06] [Error] SiteMinder Agent
PID Cache error.
Failed to initialize PID Cache
The following startup error messages:
"PID Cache error" is generated when web agent or LLAWP process is unable to create or attached to its required semaphores and shared memory segments. These are system resources required by the web agent to communicate between itself and LLAWP process to pass information.
"Error allocating shared memory segment using key" is a failure of this type can be created by the failure to create the segments or the segments being subsequently removed. As this is a startup issue it points to there being an issue with creation and the most likely reasons for this are:
To try resolving the issue, you can try the following:
The idea behind decreasing those values to 0 is to check whether your system has enough memory or not. There might be a loss of performance while those values are at 0, because there will be no caching. However if this issue disappears, then it means that you should add some memory to the system, or reduce the cache size to a lower level if adding memory isn't possible.