General Performance Tuning Guidelines for Oracle RAC.

1) Rule of thumb - It is safe to assume that an application which
scales well in a single instance environment would scale well in
a RAC environment. Opposite of that is also true, If an application
has problems with scalability in a single instance environment,
Then it may not scale well in a RAC environment.

2) Speed up instance recovery. 

i) To speed up the instance recovery time use FAST_START_MTTR_TARGET.

 In a single instance environment instance start-up + crash recovery time
 is controlled by this parameter.

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