System V and POSIX IPCs

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# 1  
Old 07-03-2002
System V and POSIX IPCs

I am using SUN 0S 5.7.
My application has a dozen programs running in this machine, each instance of a program having 2 POSIX message queues for itself. Totally around 90 POSIX message queues.

Another small application uses a SYSTEM V shared memory and a message queue.

We face a problem here...whenever we boot up the small application, several instances of the bigger application(which uses POSIX queues) were shutting down. The small application doesnt do anything other than opening a System V shared memory, writes some data in it, and detaches. All IPC keys used in all programs are unique. No signals are handled or passed to other programs. There is absolutely no link between both the applications.

Will the System V and POSIX IPCs clash on any case, when run on the same machine?

Is there different "max queues limit" parameter in the same machine for POSIX and SystemV IPCs?

# 2  
Old 07-06-2002
I think your problem is basically due to the fact that there is a limit to the number of IPC SHM that can be at any given point in time. Make sure you have configured a number good enough not to create promlems like these.
Check the /etc/system file for the configured values.

>Will the System V and POSIX IPCs clash on any case, when run on the same machine?

>Is there different "max queues limit" parameter in the same machine for POSIX and SystemV IPCs?
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