com.amazon.redshift.core.v3

Class RedshiftMemoryUtils

java.lang.Object

com.amazon.redshift.core.v3.RedshiftMemoryUtils

public final class RedshiftMemoryUtils
extends Object

Utility class for memory-related calculations in Redshift JDBC driver. Provides methods to estimate memory usage of result set data structures.

Method Summary

Modifier and Type	Method and Description
static int	calculateNodeSize(Tuple row) Calculates the estimated memory size in bytes for a tuple node, including JVM overhead.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

calculateNodeSize

public static int calculateNodeSize(Tuple row)

Calculates the estimated memory size in bytes for a tuple node, including JVM overhead. The calculation includes:

• The actual tuple data size
• JVM object overhead (32 bytes for 64-bit JVM, 16 bytes for 32-bit JVM)
• A scaling factor to account for additional JVM overhead

Note: We don't worry about overflow in this method because: - MEMORY_ESTIMATE_SCALING_FACTOR is 1.2, so even with scaling we're only increasing values by 20% - NODE_OVERHEAD is a modest constant value The main overflow risk comes from accumulating multiple tuples' sizes.

Parameters:

row - The tuple to calculate size for, can be null

Returns:

Estimated size in bytes, or 0 if the tuple is null