Compaq AAR-88LB-TE The ACP Process, Interprocess Communication, Shared Memory Parameters, 1 Cont

Architectural Changes

3.3 The Shared Library (LIBRTR.EXE)

Table 3–1 (Cont.)	RTR Executables
RTR Version 2	RTR Version 3
RTRRTL	No longer apply.

3.4 The ACP Process

The RTR Application Control Process (ACP) handles application control, and has the process name RTRACP. This is unchanged from RTR Version 2.

3.5 Interprocess Communication

In RTR Version 2, global sections (cache) were used for interprocess communication. In RTR Version 3, interprocess communication is handled with mailboxes. Each RTR process, including any application process, has three mailboxes to communicate with the RTRACP process:

•Read

•Write

•Beacon/Control

3.6Shared Memory Parameters

With RTR Version 2, the SHOW RTR/PARAMS command showed the following:

•Maximum links

•Maximum facilities

•Maximum relations

•Maximum processes

•Cache pages

The /PARAMS qualifier is obsolete in RTR Version 3, and the parameters it showed no longer apply. In RTR Version 3, these parameters are handled with OpenVMS mailboxes, which you can check using OpenVMS procedures. See the OpenVMS System Manager's Manual: Essentials for more information.

3.7 Counters

In RTR Version 2, shared memory in global sections was directly accessible using the RTR command server. In RTR Version 3, process counters are still kept in shared memory, but they are accessed from the command server through RTRACP. Thus, accessing these and other counters involves communicating with RTRACP. Other counters are contained within the address space of the ACP.

3–2Architectural Changes