In MySQL Cluster 7.5 we use Complete Checkpoints. In MySQL Cluster 7.6
we implement an approach where we only checkpoint a part of the database
in each checkpoint.
A special case is a checkpoint of a table partition where no changes
at all have happened since the last checkpoint. In this case we implemented
a special optimisation such that it is not necessary to checkpoint anything
at all for this table partition. It is only necessary to write a new LCP
control file which is 4 kBytes in size for each table partition (can grow to
8 kBytes if the recovery will require more than 980 checkpoints to
recover.
This means that if your database contains a large set of read-only tables,
there will be no need to checkpoint those tables at all. This feature
is used also when setting EnablePartialLcp to false.
we implement an approach where we only checkpoint a part of the database
in each checkpoint.
A special case is a checkpoint of a table partition where no changes
at all have happened since the last checkpoint. In this case we implemented
a special optimisation such that it is not necessary to checkpoint anything
at all for this table partition. It is only necessary to write a new LCP
control file which is 4 kBytes in size for each table partition (can grow to
8 kBytes if the recovery will require more than 980 checkpoints to
recover.
This means that if your database contains a large set of read-only tables,
there will be no need to checkpoint those tables at all. This feature
is used also when setting EnablePartialLcp to false.
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