Xenix Shared Memory Limitation

[Doug Toppin]

Help!! We have to implement a simple custom database holding
about 1.3 meg in memory (has to be kept in memory).
We have been assuming that we would allocate 21-65K shared memory 
segments and just divide up the records into the segments.
Several processes will have to have access to the data.
We just tried a simple test and we can allocate the segments with no problem.
But, when any process is run at any other terminal
while the segments exist only a shell prompt comes back.
Nothing happens, not even an error message.
If the shared memory segments are removed
by the test application everything returns to normal.
Has anyone ever seen this before? We have had isolated occurrences
where our systems will get really busy and commands have no effect.
This time it has to be fixed.
We are running IBM Xenix V on ATs with 3-meg memory.
We cannot change operating systems nor hardware.
Please reply to uunet!melpar!toppin
Useful replies will be posted. Thanks
Doug Toppin