LOG_CHECKPOINT_TIMEOUT and log switch!!
510293Aug 5 2007 — edited Aug 6 2007Hi, all.
I am a little confused between "LOG_CHECKPOINT_INTERVAL" and
"LOG_CHECKPOINT_TIMEOUT".
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Q1, what does LOG_CHECKPOINT_TIMEOUT mean?
The following is from manual, but I do not understand.
LOG_CHECKPOINT_TIMEOUT specifies (in seconds) the amount of time that has passed since the incremental checkpoint at the position where the last write to the redo log (sometimes called the tail of the log) occurred. This parameter also signifies that no buffer will remain dirty (in the cache) for more than integer seconds.
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Q2. Does Checkpoint always require "log switch"?
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Q3. From the following configuration, at what interval "log switch" occurs??
SQL>show parameter log_check
NAME TYPE VALUE
------------------------------------ ---------- -------------
log_checkpoint_interval integer 0
log_checkpoint_timeout integer 1800
log_checkpoints_to_alert boolean FALSE
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Thanks and Regards.