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How are the Number of Semaphores per set Calculated on a Unix platforms? (Doc ID 261421.1)

Last updated on FEBRUARY 03, 2019

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.1.5 to 9.2]
Information in this document applies to any platform.
Information in this document applies to any platform.


With the following parameters given, how are the number of semaphores needed by Oracle, calculated?

Unix kernel parameters:

SEMMNI = 100 # semaphore identifiers
SEMMSL = 50 # max semaphores per id or set
SEMMNS = 500 # semaphores in system

Oracle parameter:



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