Class LinuxCentralProcessor

java.lang.Object

oshi.hardware.common.AbstractCentralProcessor

oshi.hardware.common.platform.linux.LinuxCentralProcessor

All Implemented Interfaces:

CentralProcessor

Direct Known Subclasses:

LinuxCentralProcessorNF

@ThreadSafe
public abstract class LinuxCentralProcessor
extends AbstractCentralProcessor

A CPU as defined in Linux /proc.

Nested Class Summary

Nested classes/interfaces inherited from interface CentralProcessor

CentralProcessor.LogicalProcessor, CentralProcessor.PhysicalProcessor, CentralProcessor.ProcessorCache, CentralProcessor.ProcessorIdentifier, CentralProcessor.TickType

Modifier and Type	Interface	Description
static class	CentralProcessor.LogicalProcessor	A class representing a Logical Processor and its replationship to physical processors, physical packages, and logical groupings such as NUMA Nodes and Processor groups, useful for identifying processor topology.
static class	CentralProcessor.PhysicalProcessor	A class representing a Physical Processor (a core) providing per-core statistics that may vary, particularly in hybrid/modular processors.
static class	CentralProcessor.ProcessorCache	A class representing CPU Cache Memory.
static final class	CentralProcessor.ProcessorIdentifier	A class encapsulating ghe CPU's identifier strings ,including name, vendor, stepping, model, and family information (also called the signature of a CPU)
static enum	CentralProcessor.TickType	Index of CPU tick counters in the CentralProcessor.getSystemCpuLoadTicks() and CentralProcessor.getProcessorCpuLoadTicks() arrays.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LinuxCentralProcessor(long hz)	LinuxCentralProcessor.

Method Summary

Modifier and Type	Method	Description
protected static CentralProcessor.LogicalProcessor	getLogicalProcessorFromSyspath(String syspath, Set<CentralProcessor.ProcessorCache> caches, String modAlias, Map<Integer,Integer> coreEfficiencyMap, Map<Integer,String> modAliasMap)	getLogicalProcessorFromSyspath.
double[]	getSystemLoadAverage(int nelem)	Returns the system load average for the number of elements specified, up to 3, representing 1, 5, and 15 minutes.
protected Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.PhysicalProcessor>, List<CentralProcessor.ProcessorCache>, List<String>>	initProcessorCounts()	Initializes logical and physical processor lists and feature flags.
long	queryContextSwitches()	Get number of context switches
long[]	queryCurrentFreq()	Get processor current frequency.
protected static boolean	queryCurrentFreqFromSysfs(long[] freqs)	queryCurrentFreqFromSysfs.
protected abstract boolean	queryCurrentFreqFromUdev(long[] freqs)	Fills the freqs array from udev cpu-freq source.
protected long	queryHwcap()	Queries the hardware capabilities from the auxiliary vector.
long	queryInterrupts()	Get number of interrupts
long	queryMaxFreq()	Get processor max frequency.
protected static long	queryMaxFreqFromCpuFreqPath(String cpuFreqPath)	Queries the maximum frequency from a cpufreq path.
protected static long	queryMaxFreqFromSysfs()	Queries the maximum frequency from sysfs.
protected abstract long	queryMaxFreqFromUdev()	Queries the maximum frequency from udev.
long[][]	queryProcessorCpuLoadTicks()	Get the processor CPU load ticks
protected CentralProcessor.ProcessorIdentifier	queryProcessorId()	Updates logical and physical processor counts and arrays
long[]	querySystemCpuLoadTicks()	Get the system CPU load ticks
protected static Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.ProcessorCache>, Map<Integer,Integer>, Map<Integer,String>>	readTopologyFromSysfs()	Reads processor topology from sysfs using the default CPU path.
protected abstract Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.ProcessorCache>, Map<Integer,Integer>, Map<Integer,String>>	readTopologyWithUdev()	Reads processor topology using udev.

Methods inherited from class AbstractCentralProcessor

createProcessorID, createProcessorID, createProcListFromDmesg, getContextSwitches, getCurrentFreq, getFeatureFlags, getInterrupts, getLogicalProcessorCount, getLogicalProcessors, getMaxFreq, getPhysicalPackageCount, getPhysicalProcessorCount, getPhysicalProcessors, getProcessorCaches, getProcessorCpuLoadBetweenTicks, getProcessorCpuLoadBetweenTicks, getProcessorCpuLoadTicks, getProcessorIdentifier, getSystemCpuLoadBetweenTicks, getSystemCpuLoadBetweenTicks, getSystemCpuLoadTicks, orderedProcCaches, toString

Modifier and Type	Method	Description
protected static String	createProcessorID(String stepping, String model, String family, String[] flags)	Creates a Processor ID by encoding the stepping, model, family, and feature flags.
protected static String	createProcessorID(String stepping, String model, String family, String[] flags, long hwcap)	Creates a Processor ID by encoding the stepping, model, family, and feature flags.
protected List<CentralProcessor.PhysicalProcessor>	createProcListFromDmesg(List<CentralProcessor.LogicalProcessor> logProcs, Map<Integer,String> dmesg)	Creates a list of physical processors from dmesg output.
long	getContextSwitches()	Get the number of system-wide context switches which have occurred.
long[]	getCurrentFreq()	Attempts to return the current frequency (in Hz), of the logical processors on this CPU.
List<String>	getFeatureFlags()	Returns a list of platform-specific strings which identify CPU Feature Flags.
long	getInterrupts()	Get the number of system-wide interrupts which have occurred.
int	getLogicalProcessorCount()	Get the number of logical CPUs available for processing.
List<CentralProcessor.LogicalProcessor>	getLogicalProcessors()	Returns an UnmodifiableList of the CPU's logical processors.
long	getMaxFreq()	Maximum frequeny (in Hz), of the logical processors on this CPU.
int	getPhysicalPackageCount()	Get the number of packages/sockets in the system.
int	getPhysicalProcessorCount()	Get the number of physical CPUs/cores available for processing.
List<CentralProcessor.PhysicalProcessor>	getPhysicalProcessors()	Returns an UnmodifiableList of the CPU's physical processors.
List<CentralProcessor.ProcessorCache>	getProcessorCaches()	Makes a best-effort attempt to identify the CPU's processor caches.
double[]	getProcessorCpuLoadBetweenTicks(long[][] oldTicks)	Returns the "recent cpu usage" for all logical processors by counting ticks from CentralProcessor.getProcessorCpuLoadTicks() between the user-provided value from a previous call.
double[]	getProcessorCpuLoadBetweenTicks(long[][] oldTicks, long[][] ticks)	Returns the "recent cpu usage" for all logical processors by counting ticks from CentralProcessor.getProcessorCpuLoadTicks() between the user-provided value from a previous call.
long[][]	getProcessorCpuLoadTicks()	Get Processor CPU Load tick counters.
CentralProcessor.ProcessorIdentifier	getProcessorIdentifier()	The CPU's identifier strings ,including name, vendor, stepping, model, and family information (also called the signature of a CPU).
double	getSystemCpuLoadBetweenTicks(long[] oldTicks)	Returns the "recent cpu usage" for the whole system by counting ticks from CentralProcessor.getSystemCpuLoadTicks() between the user-provided value from a previous call.
double	getSystemCpuLoadBetweenTicks(long[] oldTicks, long[] ticks)	Returns the "recent cpu usage" for the whole system by counting ticks between two user-provided values, retrieved from CentralProcessor.getSystemCpuLoadTicks() at different points in time.
long[]	getSystemCpuLoadTicks()	Get System-wide CPU Load tick counters.
static List<CentralProcessor.ProcessorCache>	orderedProcCaches(Set<CentralProcessor.ProcessorCache> caches)	Filters a set of processor caches to an ordered list
String	toString()

Methods inherited from class Object

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

Methods inherited from interface CentralProcessor

getProcessorCpuLoad, getSystemCpuLoad

Modifier and Type	Method	Description
default double[]	getProcessorCpuLoad(long delay)	This is a convenience method which collects an initial set of ticks using CentralProcessor.getProcessorCpuLoadTicks() and passes that result to CentralProcessor.getProcessorCpuLoadBetweenTicks(long[][]) after the specified delay.
default double	getSystemCpuLoad(long delay)	This is a convenience method which collects an initial set of ticks using CentralProcessor.getSystemCpuLoadTicks() and passes that result to CentralProcessor.getSystemCpuLoadBetweenTicks(long[]) after the specified delay.

Constructor Details

LinuxCentralProcessor

protected LinuxCentralProcessor(long hz)

LinuxCentralProcessor.

Parameters:

hz - the hz

Method Details

queryProcessorId

protected CentralProcessor.ProcessorIdentifier queryProcessorId()

Description copied from class: AbstractCentralProcessor

Updates logical and physical processor counts and arrays

Specified by:

queryProcessorId in class AbstractCentralProcessor

Returns:

An array of initialized Logical Processors

initProcessorCounts

protected Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.PhysicalProcessor>, List<CentralProcessor.ProcessorCache>, List<String>> initProcessorCounts()

Description copied from class: AbstractCentralProcessor

Initializes logical and physical processor lists and feature flags.

Specified by:

initProcessorCounts in class AbstractCentralProcessor

Returns:

Lists of initialized Logical Processors, Physical Processors, Processor Caches, and Feature Flags.

readTopologyWithUdev

protected abstract Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.ProcessorCache>, Map<Integer,Integer>, Map<Integer,String>> readTopologyWithUdev()

Reads processor topology using udev.

Returns:

a quartet of logical processors, caches, efficiency map, and modalias map

readTopologyFromSysfs

protected static Quartet<List<CentralProcessor.LogicalProcessor>, List<CentralProcessor.ProcessorCache>, Map<Integer,Integer>, Map<Integer,String>> readTopologyFromSysfs()

Reads processor topology from sysfs using the default CPU path.

Returns:

a quartet of logical processors, caches, efficiency map, and modalias map

getLogicalProcessorFromSyspath

protected static CentralProcessor.LogicalProcessor getLogicalProcessorFromSyspath(String syspath,
 Set<CentralProcessor.ProcessorCache> caches,
 String modAlias,
 Map<Integer,Integer> coreEfficiencyMap,
 Map<Integer,String> modAliasMap)

getLogicalProcessorFromSyspath.

Parameters:

syspath - the syspath

caches - the caches

modAlias - the modAlias

coreEfficiencyMap - the coreEfficiencyMap

modAliasMap - the modAliasMap

Returns:

a LogicalProcessor for the given syspath

querySystemCpuLoadTicks

public long[] querySystemCpuLoadTicks()

Description copied from class: AbstractCentralProcessor

Get the system CPU load ticks

Specified by:

querySystemCpuLoadTicks in class AbstractCentralProcessor

Returns:

The system CPU load ticks

queryCurrentFreq

public long[] queryCurrentFreq()

Description copied from class: AbstractCentralProcessor

Get processor current frequency.

Specified by:

queryCurrentFreq in class AbstractCentralProcessor

Returns:

The current frequency.

queryCurrentFreqFromUdev

protected abstract boolean queryCurrentFreqFromUdev(long[] freqs)

Fills the freqs array from udev cpu-freq source. Returns true if successful (max > 0). Subclasses provide the implementation.

Parameters:

freqs - array to fill with per-logical-processor frequencies in Hz

Returns:

true if frequencies were successfully read

queryCurrentFreqFromSysfs

protected static boolean queryCurrentFreqFromSysfs(long[] freqs)

queryCurrentFreqFromSysfs.

Parameters:

freqs - the freqs

Returns:

the result

queryMaxFreq

public long queryMaxFreq()

Description copied from class: AbstractCentralProcessor

Get processor max frequency.

Overrides:

queryMaxFreq in class AbstractCentralProcessor

Returns:

The max frequency.

queryMaxFreqFromUdev

protected abstract long queryMaxFreqFromUdev()

Queries the maximum frequency from udev.

Returns:

the maximum frequency in Hz

queryMaxFreqFromSysfs

protected static long queryMaxFreqFromSysfs()

Queries the maximum frequency from sysfs.

Returns:

the maximum frequency in Hz

queryMaxFreqFromCpuFreqPath

protected static long queryMaxFreqFromCpuFreqPath(String cpuFreqPath)

Queries the maximum frequency from a cpufreq path.

Parameters:

cpuFreqPath - the cpufreq directory path

Returns:

the maximum frequency in Hz

getSystemLoadAverage

public double[] getSystemLoadAverage(int nelem)

Description copied from interface: CentralProcessor

Returns the system load average for the number of elements specified, up to 3, representing 1, 5, and 15 minutes. The system load average is the sum of the number of runnable entities queued to the available processors and the number of runnable entities running on the available processors averaged over a period of time.

This method is designed to provide a hint about the system load and may be queried frequently.

The way in which the load average is calculated is operating system specific but is typically a damped time-dependent average. Linux includes processes waiting for system resources such as disks, while macOS and Unix consider only processes waiting for CPU.

Windows does not provide a load average. Users may set the configuration property oshi.os.windows.loadaverage to true to start a daemon thread which will provide a similar metric.

The load average may be unavailable on some platforms (e.g., Windows without the above configuration). If the load average is not available, a negative value is returned.

Parameters:

nelem - Number of elements to return.

Returns:

an array of the system load averages for 1, 5, and 15 minutes with the size of the array specified by nelem; or negative values if not available.

queryProcessorCpuLoadTicks

public long[][] queryProcessorCpuLoadTicks()

Description copied from class: AbstractCentralProcessor

Get the processor CPU load ticks

Specified by:

queryProcessorCpuLoadTicks in class AbstractCentralProcessor

Returns:

The processor CPU load ticks

queryHwcap

protected long queryHwcap()

Queries the hardware capabilities from the auxiliary vector. Subclasses provide platform-specific implementations using JNA or FFM native access.

Returns:

The hardware capabilities value, or 0 if unavailable

queryContextSwitches

public long queryContextSwitches()

Description copied from class: AbstractCentralProcessor

Get number of context switches

Specified by:

queryContextSwitches in class AbstractCentralProcessor

Returns:

The context switches

queryInterrupts

public long queryInterrupts()

Description copied from class: AbstractCentralProcessor

Get number of interrupts

Specified by:

queryInterrupts in class AbstractCentralProcessor

Returns:

The interrupts