Solution for JQM crash caused by pdls on a loaded server

HP Output Server 3.4.1 1

Technical Update

Solution for JQM crash caused by

pdls on a loaded server

This technical update includes information related to crash of JQM server

during heavy load and submissions of pdls command. The purpose of this

technical update is to provide information about the root cause of the problem

and workaround to fix the problem using environment settings.

Platforms Affected

All

Problem

During heavy load the JQM may go into unknown status or generates a core

dump if the user tries to execute pdls command on a bunch of jobs.

This problem happens when JQM processes try to allocate memory more than

the specified data segment size, leading to process running out of memory and

JQM crash. Following are a set of options which you can try to avoid the

problem.

Increase the data segment stack size

You can increase the data segment stack size by using ulimit command.

Each operating system uses a separate data segment stack size. The following

command will help in finding the current data segment stack size

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Technical Update Solution for JQM crash caused by pdls on a loaded server This technical update includes information related to crash of JQM server during heavy load and submissions of pdls command. The purpose of this technical update is to provide information about the root cause of the problem and workaround to fix the problem using environment settings.
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HP Output Server 3.4.1 HP-UX specific Case ulimit -a Example output for ulimit -a command on Solaris: $ ulimit -a time (seconds) - unlimited file (blocks) - unlimited data (kbytes) - 96000 stack (kbytes) - 8192 coredump (blocks) - unlimited nofiles (descriptors) - 256 vmemory (kbytes) - unlimited In the above example, the data segment size is 96MB.
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Solution for JQM crash caused by pdls on a loaded server Conclusion This behavior of HP-UX memory allocator can be altered using _M_ARENA_OPTS environment variable. Example: export _M_ARENA_OPTS=1:8 Restart the JQM server and this would cause JQM server process to use single ARENA for all memory allocation requests preventing JQM server process memory from growing for any subsequent requests.
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HP Output Server 3.4.