Special Considerations for Running with Shared Memory


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When using the ch_shmem or ch_lfshmem devices with System V shared memory, processes that exit abnormally (e.g., with a segmentation violation) may leave System V semaphores or shared memory segments allocatedSurprisingly, the System V IPC (interprocess communication) mechanisms do not have a ``delete on unreferenced'' attribute. Since there is usually a limited number of these objects, it is important to recover them. The Unix command ipcs can be used to list the allocated semaphores and shared memory segments, and ipcrm can be used to delete them. The script bin/cleanipcs can be used to identify and delete all System V IPCs owned by the calling user; the use is simply

bin/cleanipcs 



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