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PARALLEL_MAX_SERVERS

PARALLEL_MAX_SERVERS The default value for  PARALLEL_MAX_SERVERS  is as follows: (CPU_COUNT x PARALLEL_THREADS_PER_CPU x (2 if PGA_AGGREGATE_TARGET > 0; otherwise 1) x 5) The value of  PGA_AGGREGATE_TARGET  can be derived when  MEMORY_TARGET  is set. See  Oracle Database Performance Tuning Guide  for descriptions of how to use  PGA_AGGREGATE_TARGET  in different scenarios. The above formula might not be sufficient for parallel queries on tables with higher degree of parallelism (DOP) attributes. We recommend users who expects to run queries of higher DOP to set  PARALLEL_MAX_SERVERS  as follows: 2 x DOP x NUMBER_OF_CONCURRENT_USERS For example, setting  PARALLEL_MAX_SERVERS  to 64 enables you to run four parallel queries simultaneously, if each query is using two slave sets with a DOP of eight for each set. When Users Have Too Many Processes When concurrent users have too many query server processes, m...