MAX_IDLE_BLOCKER_TIME sets the number of minutes that a session holding needed resources can be idle before it is a candidate for termination.
MAX_IDLE_TIME sets limits for all idle sessions, whereas
MAX_IDLE_BLOCKER_TIME sets limits only for idle sessions consuming resources.
MAX_IDLE_TIME can be problematic for a connection pool because it may continually try to re-create the sessions terminated by this parameter.
This page provides more detailed information about the new initialization parameter
MAX_IDLE_BLOCKER_TIME influencing sessions behavior.
This practice shows how to terminate a blocking session by using the new initialization parameter