public class BTreeCostModel extends Object implements Serializable
BTreebacked by a
Journal. The on disk representation of the
BTreedoes not reflect the index order so a range scan on the
BTreeis basically turned into one random seek per node or leaf visited.
|Constructor and Description|
|Modifier and Type||Method and Description|
Compute the height of the B+Tree from its entry count and branching factor (this can also be used to find the minimum height at which there could exist a given range count).
Prints out some tables based on different disk cost models, branching factors, and range scans.
Return the estimated cost of a range scan of the index.
public static int estimateHeight(int entryCount, int branchingFactor)
public double rangeScan(long rangeCount, int m, int h, int leafUtilization)
rangeCount- The range count for the scan.
m- The B+Tree branching factor.
h- The B+Tree height.
leafUtilization- The leaf utilization percentage [0:100].
public static void main(String args)
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