MPE/iX 5.5 Operating System Limits

Release 5.5 supports a maximum of 2700 active logons. The term "active" implies that
the job or session is running a program. Additionally, the process limit has increased to
8190. For planning purposes, you should allow 100 processes for the operating system's
use (this is not an exact number, but should be enough). This leaves 8090 processes for
jobs and sessions.
Each direct logon requires a minimum of 2 processes; a JSMAIN and a CI. If the job or
session runs a simple program (which does no process handling), then it requires a total
of 3 processes per logon. This allows for a maximum of approximately 2700 active
logons (3*2700=8100) with processes to spare.
It is very important to note that many applications and third party products use process
handling. You must determine how many processes will be used by each session or job in
order to accurately predict the number of jobs or sessions that the system will support.
Below is a worksheet which can be used to estimate the concurrent process requirements
for your system. If your active users are running programs which do process handling,
then you will need to change the multipliers used for active jobs and sessions.
# Active Jobs _____ x 3 = _____
# Inactive Sessions _____ (<= 2500) x 2 = _____
# Active Sessions _____ (<= 2500) x 3 = _____
+ system processes + 100
===================================================================
Total Connections _____ Total Processes _____
(<= 8190)
Although it is possible to configure more than 2500 terminal I/O devices, neither the
inactive sessions nor the active sessions should exceed 2500. An HP support
representative should be contacted before exceeding these limits.
(4) NS/concurrent processes
The exact number of remote sessions which can be supported on a given system will
depend on the exact mix of jobs and sessions (remote and local, active and inactive) on
that system.
The maximum number of concurrent processes may limit the number of remote logons
before the maximum number of data communications servers does. Likewise, the server
limit may be reached before the concurrent process limit. This section will address the
question of total concurrent jobs and sessions on a system with a mixture of local and
remote logons.