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ipcclean - Unix, Linux Command
ipcclean - remove shared memory and semaphores from a failed PostgreSQL server
ipcclean removes all shared memory segments and
semaphore sets owned by the current user. It is intended to be
used for cleaning up after a crashed
PostgreSQL server (postmaster(1)). Note that immediately restarting the
server will also clean up shared memory and semaphores, so this
command is of little real utility.
Only the database administrator should execute this program as it
can cause bizarre behavior (i.e., crashes) if run during multiuser
execution. If this command is executed while a server is running,
the shared memory and semaphores allocated by that server will be
deleted, which would have rather severe consequences for that
This script is a hack, but in the many years since it was written,
no one has come up with an equally effective and portable solution.
Since the postmaster can now clean up by
itself, it is unlikely that ipcclean will be
improved upon in the future.
The script makes assumptions about the output format of the
utility which may not be true across different operating systems.
Therefore, it may not work on your particular OS. Its wise to
look at the script before trying it.