Package org.apache.hadoop.util

Class SysInfoLinux

java.lang.Object

org.apache.hadoop.util.SysInfo

org.apache.hadoop.util.SysInfoLinux

@Private
@Evolving
public class SysInfoLinux
extends SysInfo

Plugin to calculate resource information on Linux systems.

Field Summary

Fields

Modifier and Type	Field	Description
static long	JIFFY_LENGTH_IN_MILLIS
static long	PAGE_SIZE

Constructor Summary

Constructors

Constructor	Description
SysInfoLinux()
SysInfoLinux(java.lang.String procfsMemFile, java.lang.String procfsCpuFile, java.lang.String procfsStatFile, java.lang.String procfsNetFile, java.lang.String procfsDisksFile, long jiffyLengthInMillis)	Constructor which allows assigning the /proc/ directories.

Method Summary

Modifier and Type	Method	Description
long	getAvailablePhysicalMemorySize()	Obtain the total size of the available physical memory present in the system.
long	getAvailableVirtualMemorySize()	Obtain the total size of the available virtual memory present in the system.
long	getCpuFrequency()	Obtain the CPU frequency of on the system.
float	getCpuUsagePercentage()	Obtain the CPU usage % of the machine.
long	getCumulativeCpuTime()	Obtain the cumulative CPU time since the system is on.
long	getJiffyLengthInMillis()
long	getNetworkBytesRead()	Obtain the aggregated number of bytes read over the network.
long	getNetworkBytesWritten()	Obtain the aggregated number of bytes written to the network.
int	getNumCores()	Obtain total number of physical cores present on the system.
int	getNumProcessors()	Obtain the total number of logical processors present on the system.
float	getNumVCoresUsed()	Obtain the number of VCores used.
long	getPhysicalMemorySize()	Obtain the total size of the physical memory present in the system.
long	getStorageBytesRead()	Obtain the aggregated number of bytes read from disks.
long	getStorageBytesWritten()	Obtain the aggregated number of bytes written to disks.
long	getVirtualMemorySize()	Obtain the total size of the virtual memory present in the system.
static void	main(java.lang.String[] args)	Test the SysInfoLinux.

Methods inherited from class org.apache.hadoop.util.SysInfo

newInstance

Methods inherited from class java.lang.Object

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

Field Detail

PAGE_SIZE

public static final long PAGE_SIZE

JIFFY_LENGTH_IN_MILLIS

public static final long JIFFY_LENGTH_IN_MILLIS

Constructor Detail

SysInfoLinux

public SysInfoLinux()

SysInfoLinux

@VisibleForTesting
public SysInfoLinux(java.lang.String procfsMemFile,
                    java.lang.String procfsCpuFile,
                    java.lang.String procfsStatFile,
                    java.lang.String procfsNetFile,
                    java.lang.String procfsDisksFile,
                    long jiffyLengthInMillis)

Constructor which allows assigning the /proc/ directories. This will be used only in unit tests.

Parameters:

procfsMemFile - fake file for /proc/meminfo

procfsCpuFile - fake file for /proc/cpuinfo

procfsStatFile - fake file for /proc/stat

procfsNetFile - fake file for /proc/net/dev

procfsDisksFile - fake file for /proc/diskstats

jiffyLengthInMillis - fake jiffy length value

Method Detail

getPhysicalMemorySize

public long getPhysicalMemorySize()

Obtain the total size of the physical memory present in the system.

Specified by:

getPhysicalMemorySize in class SysInfo

Returns:

physical memory size bytes.

getVirtualMemorySize

public long getVirtualMemorySize()

Obtain the total size of the virtual memory present in the system.

Specified by:

getVirtualMemorySize in class SysInfo

Returns:

virtual memory size in bytes.

getAvailablePhysicalMemorySize

public long getAvailablePhysicalMemorySize()

Obtain the total size of the available physical memory present in the system.

Specified by:

getAvailablePhysicalMemorySize in class SysInfo

Returns:

available physical memory size bytes.

getAvailableVirtualMemorySize

public long getAvailableVirtualMemorySize()

Obtain the total size of the available virtual memory present in the system.

Specified by:

getAvailableVirtualMemorySize in class SysInfo

Returns:

available virtual memory size in bytes.

getNumProcessors

public int getNumProcessors()

Obtain the total number of logical processors present on the system.

Specified by:

getNumProcessors in class SysInfo

Returns:

number of logical processors

getNumCores

public int getNumCores()

Obtain total number of physical cores present on the system.

Specified by:

getNumCores in class SysInfo

Returns:

number of physical cores

getCpuFrequency

public long getCpuFrequency()

Obtain the CPU frequency of on the system.

Specified by:

getCpuFrequency in class SysInfo

Returns:

CPU frequency in kHz

getCumulativeCpuTime

public long getCumulativeCpuTime()

Obtain the cumulative CPU time since the system is on.

Specified by:

getCumulativeCpuTime in class SysInfo

Returns:

cumulative CPU time in milliseconds

getCpuUsagePercentage

public float getCpuUsagePercentage()

Obtain the CPU usage % of the machine. Return -1 if it is unavailable

Specified by:

getCpuUsagePercentage in class SysInfo

Returns:

CPU usage as a percentage (from 0 to 100) of available cycles.

getNumVCoresUsed

public float getNumVCoresUsed()

Obtain the number of VCores used. Return -1 if it is unavailable

Specified by:

getNumVCoresUsed in class SysInfo

Returns:

Number of VCores used a percentage (from 0 to #VCores).

getNetworkBytesRead

public long getNetworkBytesRead()

Obtain the aggregated number of bytes read over the network.

Specified by:

getNetworkBytesRead in class SysInfo

Returns:

total number of bytes read.

getNetworkBytesWritten

public long getNetworkBytesWritten()

Obtain the aggregated number of bytes written to the network.

Specified by:

getNetworkBytesWritten in class SysInfo

Returns:

total number of bytes written.

getStorageBytesRead

public long getStorageBytesRead()

Description copied from class: SysInfo

Obtain the aggregated number of bytes read from disks.

Specified by:

getStorageBytesRead in class SysInfo

Returns:

total number of bytes read.

getStorageBytesWritten

public long getStorageBytesWritten()

Description copied from class: SysInfo

Obtain the aggregated number of bytes written to disks.

Specified by:

getStorageBytesWritten in class SysInfo

Returns:

total number of bytes written.

main

public static void main(java.lang.String[] args)

Test the SysInfoLinux.

Parameters:

args - - arguments to this calculator test

getJiffyLengthInMillis

public long getJiffyLengthInMillis()