Solution for JQM crash caused by pdls on a loaded server

HP Output Server 3.4.1 3

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.

NOTE: The same can be achieved for a specific server by

setting this variable in

-server-environment-variables attribute for a

server. Setting of _M_ARENA_OPTS variable may adversely

affect the performance of an application, as per HP-UX

manual for “malloc”, use of different ARENA for each

thread leads to better performance.

The M_ARENA_OPTS can also be set for a specific server (JQM or any other)

by using -server-environment-variables attribute and can be set

using the following command

config_server -u -x"-server-environment-variables

\"_M_ARENA_OPTS=1:8\"" jqm

Conclusion

With all this being said, the JQM design has a limitation where it buffers all the

output for pdls in it’s memory prior to marshalling the data to the pdls client.

This could cause JQM to crash for large number of jobs. The only way to avoid

the crash is to increase “data segment size” (this can only reduce the

probability of server crash) or avoid issuing pdls on bunch of jobs.