Check for parameter fast_start_mttr_target

Success Factor COMPUTER FAILURE PREVENTION BEST PRACTICES
Recommendation
Benefit / Impact:

To optimize run time performance for write/redo generation intensive workloads.  Increasing fast_start_mttr_target from the default will reduce checkpoint writes from DBWR processes, making more room for LGWR IO.

Risk:

Performance implications if set too aggressively (lower setting = more aggressive), but a trade-off between performance and availability.  This trade-off and the type of workload needs to be evaluated and a decision made whether the default is needed to meet RTO objectives.  fast_start_mttr_target should be set to the desired RTO (Recovery Time Objective) while still maintaing performance SLAs. So this needs to be evaluated on a case by case basis.

Action / Repair:

Consider increasing fast_start_mttr_target to 300 (five minutes) from the default. The trade-off is that instance recovery will run longer, so if instance recovery is more important than performance, then keep fast_start_mttr_target at the default.

Keep in mind that an application with inadequately sized redo logs will likley not see an affect from this change due to frequent log switches so follow best practices for sizing redo logs.

Considerations for a direct writes in a data warehouse type of application: Even though direct operations aren't using the buffer cache, fast_start_mttr_target is very effective at controlling crash recovery time because it ensures adequate checkpointing for the few buffers that are resident (ex: undo segment headers).
Needs attention on rcaaa2, rcsm2, rcaaa1, rcsm1
Passed on

 

Status on rcaaa2:
WARNING => fast_start_mttr_target should be greater than or equal to 300.
rcaaa2.fast_start_mttr_target = 0

 

Status on rcsm2:
WARNING => fast_start_mttr_target should be greater than or equal to 300.
rcsm2.fast_start_mttr_target = 0
Status on rcaaa1:
WARNING => fast_start_mttr_target should be greater than or equal to 300.
rcaaa1.fast_start_mttr_target = 0

 

Status on rcsm1:
WARNING => fast_start_mttr_target should be greater than or equal to 300.
rcsm1.fast_start_mttr_target = 0

http://ravikishoredba.blogspot.in/2012/12/faststartmttrtarget-in-redo-log-tunning.html

https://docs.oracle.com/cd/E18283_01/server.112/e17110/initparams131.htm

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