Semaphores

Semaphores, unlike message queues and pipes, are not used for exchanging data, but as a means of synchronizing operations among processes. Semaphores provide the ability to perform serialization on resources. A semaphore value is stored in the kernel and then set, read, and reset by sharing processes according to some defined scheme.

Typical uses for semaphores are serialization of shared memory, resource counting, and file locking. Frequently, semaphores are used to serialize hunks of shared memory.

Use this panel to select your semaphore limits.

You can find more detailed help on the following elements of this window:

Number of unique semaphore sets on this system (IPCSEMNIDS)

Number of semaphores per set (IPCSEMNSEMS)

Number of operations per semaphore call (IPCSEMNOPS)