Automatic checkpoint tuning in 10g?

Does anyone have an idea with the following sentence?
Automatic checkpoint tuning is enabled when FAST_START_MTTR_TARGET is not explicitly set to zero.
I think the incremental checkpoint event was introduced in 9i...But I saw this automatic checkpoint tuning feature in the 10g OTN doc. what's new?
Anyway!! we need to set this parameter with a non-zero value to use the incremental checkpoint event though.

hi,
Since Oracle 9i FAST_START_MTTR_TARGET parameter is the preferred method
of tuning incremental checkpoint target. FAST_START_MTTR_TARGET enables you to specify the number of seconds the database takes to perform crash recovery of a single instance. Based on internal statistics, incremental checkpoint
automatically adjusts the checkpoint target to meet the requirement of
FAST_START_MTTR_TARGET.
V$INSTANCE_RECOVERY.ESTIMATED_MTTR shows the current estimated mean time to
recover (MTTR) in seconds. This value is shown even if FAST_START_MTTR_TARGET
is not specified.
V$INSTANCE_RECOVERY.TARGET_MTTR shows the effective MTTR target in seconds
enforced by the system.
V$MTTR_TARGET_ADVICE shows the number of I/Os resulted by the current workload
under the current MTTR setting and the estimated number of I/Os that would be
resulted by the current workload under other MTTR settings.
so I would recommend you run this sql to find out what the system thinks your MTTR_TARGET should be.
If FAST_START_MTTR_TARGET is specified, LOG_CHECKPOINT_INTERVAL should not
be set or set to 0.
rgds
alan

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--neeraj                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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