Maximum Amount of Shared Memory for One Process

Check that the maximum amount of memory that can be allocated for one process is equal to the total addressable shared-memory size for a single operating-system process. The following equation expresses the concept another way:

Maximum amount of shared memory for one process =
   (Maximum number of attached shared-memory segments per
   process) x (Maximum shared-memory segment size)

If this relationship does not hold, one of two undesirable situations could develop:

• If the total amount of shared memory is less than the total addressable shared-memory size, you can address more shared memory for the operating system than is available.
• If the total amount of shared memory is greater than the total addressable size of shared memory, you can never address some amount of shared memory that is available. That is, space that could potentially be used as shared memory cannot be allocated.