Class RamUsageEstimator

Estimates the size (memory representation) of .NET objects.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Inheritance
object
RamUsageEstimator
Inherited Members
Namespace: Lucene.Net.Util
Assembly: Lucene.Net.dll
Syntax
public sealed class RamUsageEstimator

Fields

NUM_BYTES_ARRAY_HEADER

Number of bytes to represent an array header (no content, but with alignments).

Declaration
public static readonly int NUM_BYTES_ARRAY_HEADER
Field Value
Type Description
int
See Also

NUM_BYTES_BOOLEAN

Estimates the size (memory representation) of .NET objects.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Declaration
public const int NUM_BYTES_BOOLEAN = 1
Field Value
Type Description
int
See Also

NUM_BYTES_BYTE

Estimates the size (memory representation) of .NET objects.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Declaration
public const int NUM_BYTES_BYTE = 1
Field Value
Type Description
int
See Also

NUM_BYTES_CHAR

Estimates the size (memory representation) of .NET objects.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Declaration
public const int NUM_BYTES_CHAR = 2
Field Value
Type Description
int
See Also

NUM_BYTES_DOUBLE

Estimates the size (memory representation) of .NET objects.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Declaration
public const int NUM_BYTES_DOUBLE = 8
Field Value
Type Description
int
See Also

NUM_BYTES_INT16

NOTE: This was NUM_BYTES_SHORT in Lucene

Declaration
public const int NUM_BYTES_INT16 = 2
Field Value
Type Description
int
See Also

NUM_BYTES_INT32

NOTE: This was NUM_BYTES_INT in Lucene

Declaration
public const int NUM_BYTES_INT32 = 4
Field Value
Type Description
int
See Also

NUM_BYTES_INT64

NOTE: This was NUM_BYTES_LONG in Lucene

Declaration
public const int NUM_BYTES_INT64 = 8
Field Value
Type Description
int
See Also

NUM_BYTES_OBJECT_ALIGNMENT

A constant specifying the object alignment boundary inside the .NET runtime. Objects will always take a full multiple of this constant, possibly wasting some space.

Declaration
public static readonly int NUM_BYTES_OBJECT_ALIGNMENT
Field Value
Type Description
int
See Also

NUM_BYTES_OBJECT_HEADER

Number of bytes to represent an object header (no fields, no alignments).

Declaration
public static readonly int NUM_BYTES_OBJECT_HEADER
Field Value
Type Description
int
See Also

NUM_BYTES_OBJECT_REF

Number of bytes this .NET runtime uses to represent an object reference.

Declaration
public static readonly int NUM_BYTES_OBJECT_REF
Field Value
Type Description
int
See Also

NUM_BYTES_SINGLE

NOTE: This was NUM_BYTES_FLOAT in Lucene

Declaration
public const int NUM_BYTES_SINGLE = 4
Field Value
Type Description
int
See Also

ONE_GB

One gigabyte bytes.

Declaration
public const long ONE_GB = 1073741824
Field Value
Type Description
long
See Also

ONE_KB

One kilobyte bytes.

Declaration
public const long ONE_KB = 1024
Field Value
Type Description
long
See Also

ONE_MB

One megabyte bytes.

Declaration
public const long ONE_MB = 1048576
Field Value
Type Description
long
See Also

Methods

AlignObjectSize(long)

Aligns an object size to be the next multiple of NUM_BYTES_OBJECT_ALIGNMENT.

Declaration
public static long AlignObjectSize(long size)
Parameters
Type Name Description
long size
Returns
Type Description
long
See Also

HumanReadableUnits(long)

Returns size in human-readable units (GB, MB, KB or bytes).

Declaration
public static string HumanReadableUnits(long bytes)
Parameters
Type Name Description
long bytes
Returns
Type Description
string
See Also

HumanReadableUnits(long, IFormatProvider)

Returns size in human-readable units (GB, MB, KB or bytes).

Declaration
public static string HumanReadableUnits(long bytes, IFormatProvider df)
Parameters
Type Name Description
long bytes
IFormatProvider df
Returns
Type Description
string
See Also

HumanSizeOf(object)

Return a human-readable size of a given object.

Declaration
public static string HumanSizeOf(object @object)
Parameters
Type Name Description
object object
Returns
Type Description
string
See Also

HumanSizeOf(object, IFormatProvider)

Return a human-readable size of a given object.

Declaration
public static string HumanSizeOf(object @object, IFormatProvider df)
Parameters
Type Name Description
object object
IFormatProvider df
Returns
Type Description
string
See Also

ShallowSizeOf(object)

Estimates a "shallow" memory usage of the given object. For arrays, this will be the memory taken by array storage (no subreferences will be followed). For objects, this will be the memory taken by the fields.

.NET object alignments are also applied.
Declaration
public static long ShallowSizeOf(object obj)
Parameters
Type Name Description
object obj
Returns
Type Description
long
See Also

ShallowSizeOfInstance(Type)

Returns the shallow instance size in bytes an instance of the given class would occupy. This works with all conventional classes and primitive types, but not with arrays (the size then depends on the number of elements and varies from object to object).

Declaration
public static long ShallowSizeOfInstance(Type clazz)
Parameters
Type Name Description
Type clazz
Returns
Type Description
long
Exceptions
Type Condition
ArgumentException

if clazz is an array class.
See Also

SizeOf(bool[])

Returns the size in bytes of the bool[] object.

Declaration
public static long SizeOf(bool[] arr)
Parameters
Type Name Description
bool[] arr
Returns
Type Description
long
See Also

SizeOf(byte[])

Returns the size in bytes of the byte[] object.

Declaration
public static long SizeOf(byte[] arr)
Parameters
Type Name Description
byte[] arr
Returns
Type Description
long
See Also

SizeOf(char[])

Returns the size in bytes of the char[] object.

Declaration
public static long SizeOf(char[] arr)
Parameters
Type Name Description
char[] arr
Returns
Type Description
long
See Also

SizeOf(double[])

Returns the size in bytes of the double[] object.

Declaration
public static long SizeOf(double[] arr)
Parameters
Type Name Description
double[] arr
Returns
Type Description
long
See Also

SizeOf(short[])

Returns the size in bytes of the short[] object.

Declaration
public static long SizeOf(short[] arr)
Parameters
Type Name Description
short[] arr
Returns
Type Description
long
See Also

SizeOf(int[])

Returns the size in bytes of the int[] object.

Declaration
public static long SizeOf(int[] arr)
Parameters
Type Name Description
int[] arr
Returns
Type Description
long
See Also

SizeOf(long[])

Returns the size in bytes of the long[] object.

Declaration
public static long SizeOf(long[] arr)
Parameters
Type Name Description
long[] arr
Returns
Type Description
long
See Also

SizeOf(object)

Estimates the RAM usage by the given object. It will walk the object tree and sum up all referenced objects.

Resource Usage: this method internally uses a set of every object seen during traversals so it does allocate memory (it isn't side-effect free). After the method exits, this memory should be GCed.

Declaration
public static long SizeOf(object obj)
Parameters
Type Name Description
object obj
Returns
Type Description
long
See Also

SizeOf(sbyte[])

Returns the size in bytes of the sbyte[] object.

Declaration
[CLSCompliant(false)]
public static long SizeOf(sbyte[] arr)
Parameters
Type Name Description
sbyte[] arr
Returns
Type Description
long
See Also

SizeOf(float[])

Returns the size in bytes of the float[] object.

Declaration
public static long SizeOf(float[] arr)
Parameters
Type Name Description
float[] arr
Returns
Type Description
long
See Also

SizeOf(ushort[])

Returns the size in bytes of the ushort[] object.

Declaration
[CLSCompliant(false)]
public static long SizeOf(ushort[] arr)
Parameters
Type Name Description
ushort[] arr
Returns
Type Description
long
See Also

SizeOf(uint[])

Returns the size in bytes of the uint[] object.

Declaration
[CLSCompliant(false)]
public static long SizeOf(uint[] arr)
Parameters
Type Name Description
uint[] arr
Returns
Type Description
long
See Also

SizeOf(ulong[])

Returns the size in bytes of the ulong[] object.

Declaration
[CLSCompliant(false)]
public static long SizeOf(ulong[] arr)
Parameters
Type Name Description
ulong[] arr
Returns
Type Description
long
See Also

See Also