org.ojalgo.concurrent
Class Hardware

java.lang.Object
  org.ojalgo.concurrent.Hardware

public final class Hardware
extends Object

• The first element in the array should correspond to total system resources; the total amount of RAM and the total number of threads (Typically the same as what is returned by Runtime.availableProcessors()).
• The last element in the array should describe the L1 cache. Typically Intel processors have 32k L1 cache and AMD 64k. 1 or maybe 2 threads use/share this cache.
• Caches, all levels except L1, are described between the first and last elements in descending order (L3 cache comes before L2 cache). Specify the size of the cache and the number of threads using/sharing the cache. (Do not worry about how many cache units there are - describe one unit.)
• The array must have at least 2 elements. You must describe the total system resources and the L1 cache. It is strongly recommended to also describe the L2 cache. The L3 cache, if it exists, is less important to describe. The derived attributes processors, cores and units may be incorrectly calculated if you fail to specify the caches. Known issue: If you have more than one processor, nut no L3 cache; the processors attribute will be incorrectly set 1. A workaround that currently works is to define an L3 cache anyway and set the memory/size of that cache to 0bytes. This workoround may stop working in the future.
• new MemoryThreads[] { SYSTEM, L3, L2, L1 } or new MemoryThreads[] { SYSTEM, L2, L1 } or new MemoryThreads[] { SYSTEM, L1 }

Author:

apete

Nested Class Summary

static class

Hardware.MemoryThreads How much memory, and how many threads share that memory.

Field Summary

long	cache The size of one L2 cache unit in bytes.
int	cores The total number of processor cores.
int	dim The dimension (size) of the largest square matrix that will fit in an L2 cache.
int	elements The largest number of matrix elements that will fit in an L2 cache
static Hardware	I7_620M Peter Abeles's (EJML) Intel Core i7-620M laptop 1 processor 2 cores per processor 2 threads per core Total 4 threads 8GB RAM 4MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core
static Hardware	I7_920 Holger Arndt's (UJMP) Intel Core i7-920 server 1 processor 4 cores per processor 2 threads per core Total 8 threads 8GB RAM 8MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core
static Hardware	INTEL1 1 processor 1 core per processor 1 thread per core Total 1 threads 1GB RAM 1MB L2 cache per processor 32kB L1 cache per core
static Hardware	MANTA 1 processor 2 cores per processor 1 thread per core Total 2 threads 4GB RAM (MANTA: 3GB, B5950053: 3.5GB) 4MB L2 cache per processor (MANTA: 4MB, B5950053: 6MB) 32kB L1 cache per core
long	memory Total amount of system RAM in bytes
int	processors The number of L3 cache units.
static Hardware	QXX00 Peter Abeles' (EJML) Q9400 and Q6600 machines.
static Hardware	SAILFISH 2 processors 4 cores per processor 2 threads per core Total 16 threads 12GB RAM 8MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core
int	threads Total number of threads handled by the system.
int	units The number of L2 cache units.

Constructor Summary

Hardware(Hardware.MemoryThreads[] someLevels)
new MemoryThreads[] { SYSTEM, L3, L2, L1 } or new MemoryThreads[] { SYSTEM, L2, L1 } or in worst case new MemoryThreads[] { SYSTEM, L1 }

Method Summary

int	countThreadsPerCore()
int	countThreadsPerProcessor()
int	countThreadsPerUnit()
boolean	isL2Specified()
boolean	isL3Specified()
boolean	isMultiCore()
boolean	isMultiProcessor()
boolean	isMultiUnit()
static Hardware	makeSimple(long systemRAM, int systemThreads)
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

I7_620M

public static final Hardware I7_620M

Peter Abeles's (EJML) Intel Core i7-620M laptop 1 processor 2 cores per processor 2 threads per core Total 4 threads 8GB RAM 4MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core

I7_920

public static final Hardware I7_920

Holger Arndt's (UJMP) Intel Core i7-920 server 1 processor 4 cores per processor 2 threads per core Total 8 threads 8GB RAM 8MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core

INTEL1

public static final Hardware INTEL1

1 processor 1 core per processor 1 thread per core Total 1 threads 1GB RAM 1MB L2 cache per processor 32kB L1 cache per core

MANTA

public static final Hardware MANTA

1 processor 2 cores per processor 1 thread per core Total 2 threads 4GB RAM (MANTA: 3GB, B5950053: 3.5GB) 4MB L2 cache per processor (MANTA: 4MB, B5950053: 6MB) 32kB L1 cache per core

QXX00

public static final Hardware QXX00

Peter Abeles' (EJML) Q9400 and Q6600 machines. 1 processor 4 cores per processor 1 thread per core Total 4 threads 8GB RAM (Q6600: 8GB, Q9400: 3GB) 3MB L2 cache per 2 cores (Q6600: 2x4MB, Q9400: 2x3MB) 32kB L1 cache per core

SAILFISH

public static final Hardware SAILFISH

2 processors 4 cores per processor 2 threads per core Total 16 threads 12GB RAM 8MB L3 cache per processor 256kB L2 cache per core 32kB L1 cache per core

cache

public final long cache

The size of one L2 cache unit in bytes. If no L2 cache is specified then this will be equal to memory.

cores

public final int cores

The total number of processor cores.

dim

public final int dim

The dimension (size) of the largest square matrix that will fit in an L2 cache.

elements

public final int elements

The largest number of matrix elements that will fit in an L2 cache

memory

public final long memory

Total amount of system RAM in bytes

processors

public final int processors

The number of L3 cache units. (It is assumed there is 1 L3 cache unit per processor.) If no L3 cache is specified then this will be equal to units.

threads

public final int threads

Total number of threads handled by the system.

See Also:

Runtime.availableProcessors()

units

public final int units

The number of L2 cache units. If no L2 cache is specified then this will be equal to 1.

Constructor Detail

Hardware

public Hardware(Hardware.MemoryThreads[] someLevels)

new MemoryThreads[] { SYSTEM, L3, L2, L1 } or new MemoryThreads[] { SYSTEM, L2, L1 } or in worst case new MemoryThreads[] { SYSTEM, L1 }

Method Detail

makeSimple

public static Hardware makeSimple(long systemRAM,
                                  int systemThreads)

countThreadsPerCore

public int countThreadsPerCore()

countThreadsPerProcessor

public int countThreadsPerProcessor()

countThreadsPerUnit

public int countThreadsPerUnit()

isL2Specified

public boolean isL2Specified()

isL3Specified

public boolean isL3Specified()

isMultiCore

public boolean isMultiCore()

isMultiProcessor

public boolean isMultiProcessor()

isMultiUnit

public boolean isMultiUnit()

toString

public String toString()

Overrides:

toString in class Object