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8.2. The SEMMNI Parameter

This parameter defines the maximum number of semaphore sets for the entire Linux system.
Oracle recommends SEMMNI to be at least 128 for 9i R2 and 10g R1/R2 databases except for 9i R2 on x86 platforms where the minimum value is lower. Since these recommendations are minimum settings, it is best to set it always to at least 128 for 9i and 10g databases on x86 and x86-64 platforms.