Reset "_gc_policy_minimum" parameter to its default.

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No more frequent remastering of objects.

As default value of "_gc_policy_minimum"(formerly known as _gc_affinity_minimum) is quite low for busy environments,

Those who are setting this parameter to 15000 according to the Best Practices and Recommendations for RAC databases with SGA size over 100GB (Doc ID 1619155.1), I have good news for you. 

Reset "_gc_policy_minimum" parameter


From 19.20 (19c DBRU JUL '23) on, You may reset it to its default value. 

Due to internal bug 34729755, 15000 is the new default in 23c, 19c DBRU JUL '23, and 19c ADB.  DBAs having compulsive tuning disorder like me won't have to tune this parameter any more in those releases or later.

According to the  DRM - Dynamic Resource management (Doc ID 390483.1), DRM attributes are intentionally undocumented since they may change depending on the version. These attributes should not be changed without discussing with Support.

You can access much more information about the Dynamic Resource management from the "RAC object remastering ( Dynamic remastering )" blog post by Riyaj Shamsudeen, IMO still the best after more than 10 years.

Hope it helps.

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