When the EnableIPC configuration item is set to a value other than zero eloqdb6 may use shared memory for communiation between the client and server.

Depending on the application this results in a noticeable reduction of system time and increase in performance.

• EnableIPC = 0 (default)
  Disables use of shared memory communication.

• EnableIPC = 1
  enables use of shared memory communication. This mode uses a separate memory segment for each connection. This mode is known to cause a performance problem on HP-UX with larger configurations.

• EnableIPC = 2 (recommended)
  enables use of shared memory communication. This mode uses a common memory segment for all connections.

When using EnableIPC configuration of kernel parameters may be needed. Each connection uses a semaphore and with EnableIPC = 1 a separate shared memory is allocated.

The main difference between EnableIPC modes 1 and 2 is that mode 2 uses a common shared memory segment for all connections where mode 1 allocates a separate one for each connection.
Using a common shared memory segment for all connections improves performance but has the theoretical disadvantage that an application program could corrupt information regarding a different connection. However this is very unlikely and has not been observed in practice.

NOTE:

• EnableIPC has no effect on the Windows platform.
• EnableIPC = 2 requires installation of eloqdb6 patch PE70-0305270 or newer.