CentralProcessor.java
/**
* Oshi (https://github.com/dblock/oshi)
*
* Copyright (c) 2010 - 2015 The Oshi Project Team
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* dblock[at]dblock[dot]org
* alessandro[at]perucchi[dot]org
* widdis[at]gmail[dot]com
* https://github.com/dblock/oshi/graphs/contributors
*/
package oshi.software.os.linux.proc;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import oshi.hardware.Processor;
import oshi.util.FileUtil;
import oshi.util.ParseUtil;
/**
* A CPU as defined in Linux /proc.
*
* @author alessandro[at]perucchi[dot]org
* @author alessio.fachechi[at]gmail[dot]com
* @author widdis[at]gmail[dot]com
*/
@SuppressWarnings("restriction")
public class CentralProcessor implements Processor {
// Determine whether MXBean supports Oracle JVM methods
private static final java.lang.management.OperatingSystemMXBean OS_MXBEAN = ManagementFactory
.getOperatingSystemMXBean();;
private static boolean sunMXBean;
static {
try {
Class.forName("com.sun.management.OperatingSystemMXBean");
// Initialize CPU usage
((com.sun.management.OperatingSystemMXBean) OS_MXBEAN)
.getSystemCpuLoad();
sunMXBean = true;
} catch (ClassNotFoundException e) {
sunMXBean = false;
}
}
// Maintain two sets of previous ticks to be used for calculating usage
// between them.
// System ticks (static)
private static long tickTime = System.currentTimeMillis();
private static long[] prevTicks = new long[4];
private static long[] curTicks = new long[4];
static {
updateSystemTicks();
System.arraycopy(curTicks, 0, prevTicks, 0, curTicks.length);
}
// Maintain similar arrays for per-processor ticks (class variables)
private long procTickTime = System.currentTimeMillis();
private long[] prevProcTicks = new long[4];
private long[] curProcTicks = new long[4];
// Initialize numCPU
private static int numCPU = 0;
static {
try {
List<String> procCpu = FileUtil.readFile("/proc/cpuinfo");
for (String cpu : procCpu) {
if (cpu.startsWith("core id")) {
numCPU++;
}
}
} catch (IOException e) {
System.err.println("Problem with: /proc/cpuinfo");
System.err.println(e.getMessage());
}
}
// Set up array to maintain current ticks for rapid reference. This array
// will be updated in place and used as a cache to avoid rereading file
// while iterating processors
private static long[][] allProcessorTicks = new long[numCPU][4];
private static long allProcTickTime = 0;
private int processorNumber;
private String cpuVendor;
private String cpuName;
private String cpuIdentifier = null;
private String cpuStepping;
private String cpuModel;
private String cpuFamily;
private Long cpuVendorFreq = null;
private Boolean cpu64;
/**
* Create a Processor with the given number
*
* @param procNo
*/
public CentralProcessor(int procNo) {
if (procNo >= numCPU)
throw new IllegalArgumentException("Processor number (" + procNo
+ ") must be less than the number of CPUs: " + numCPU);
this.processorNumber = procNo;
updateProcessorTicks();
System.arraycopy(allProcessorTicks[processorNumber], 0, curProcTicks,
0, curProcTicks.length);
}
/**
* {@inheritDoc}
*/
@Override
public int getProcessorNumber() {
return processorNumber;
}
/**
* Vendor identifier, eg. GenuineIntel.
*
* @return Processor vendor.
*/
@Override
public String getVendor() {
return this.cpuVendor;
}
/**
* Set processor vendor.
*
* @param vendor
* Vendor.
*/
@Override
public void setVendor(String vendor) {
this.cpuVendor = vendor;
}
/**
* Name, eg. Intel(R) Core(TM)2 Duo CPU T7300 @ 2.00GHz
*
* @return Processor name.
*/
@Override
public String getName() {
return this.cpuName;
}
/**
* Set processor name.
*
* @param name
* Name.
*/
@Override
public void setName(String name) {
this.cpuName = name;
}
/**
* Vendor frequency (in Hz), eg. for processor named Intel(R) Core(TM)2 Duo
* CPU T7300 @ 2.00GHz the vendor frequency is 2000000000.
*
* @return Processor frequency or -1 if unknown.
*/
@Override
public long getVendorFreq() {
if (this.cpuVendorFreq == null) {
Pattern pattern = Pattern.compile("@ (.*)$");
Matcher matcher = pattern.matcher(getName());
if (matcher.find()) {
String unit = matcher.group(1);
this.cpuVendorFreq = Long.valueOf(ParseUtil.parseHertz(unit));
} else {
this.cpuVendorFreq = Long.valueOf(-1L);
}
}
return this.cpuVendorFreq.longValue();
}
/**
* Set vendor frequency.
*
* @param freq
* Frequency.
*/
@Override
public void setVendorFreq(long freq) {
this.cpuVendorFreq = Long.valueOf(freq);
}
/**
* Identifier, eg. x86 Family 6 Model 15 Stepping 10.
*
* @return Processor identifier.
*/
@Override
public String getIdentifier() {
if (this.cpuIdentifier == null) {
StringBuilder sb = new StringBuilder();
if (getVendor().contentEquals("GenuineIntel"))
sb.append(isCpu64bit() ? "Intel64" : "x86");
else
sb.append(getVendor());
sb.append(" Family ");
sb.append(getFamily());
sb.append(" Model ");
sb.append(getModel());
sb.append(" Stepping ");
sb.append(getStepping());
this.cpuIdentifier = sb.toString();
}
return this.cpuIdentifier;
}
/**
* Set processor identifier.
*
* @param identifier
* Identifier.
*/
@Override
public void setIdentifier(String identifier) {
this.cpuIdentifier = identifier;
}
/**
* Is CPU 64bit?
*
* @return True if cpu is 64bit.
*/
@Override
public boolean isCpu64bit() {
return this.cpu64.booleanValue();
}
/**
* Set flag is cpu is 64bit.
*
* @param cpu64
* True if cpu is 64.
*/
@Override
public void setCpu64(boolean cpu64) {
this.cpu64 = Boolean.valueOf(cpu64);
}
/**
* @return the stepping
*/
@Override
public String getStepping() {
return this.cpuStepping;
}
/**
* @param stepping
* the stepping to set
*/
@Override
public void setStepping(String stepping) {
this.cpuStepping = stepping;
}
/**
* @return the model
*/
@Override
public String getModel() {
return this.cpuModel;
}
/**
* @param model
* the model to set
*/
@Override
public void setModel(String model) {
this.cpuModel = model;
}
/**
* @return the family
*/
@Override
public String getFamily() {
return this.cpuFamily;
}
/**
* @param family
* the family to set
*/
@Override
public void setFamily(String family) {
this.cpuFamily = family;
}
/**
* {@inheritDoc}
*/
@Override
@Deprecated
public float getLoad() {
// TODO Remove in 2.0
return (float) getSystemCpuLoadBetweenTicks() * 100;
}
/**
* {@inheritDoc}
*/
@Override
public double getSystemCpuLoadBetweenTicks() {
// Check if > ~ 0.95 seconds since last tick count.
long now = System.currentTimeMillis();
boolean update = (now - tickTime > 950);
if (update) {
// Enough time has elapsed.
// Update latest
updateSystemTicks();
tickTime = now;
}
// Calculate total
long total = 0;
for (int i = 0; i < curTicks.length; i++) {
total += (curTicks[i] - prevTicks[i]);
}
// Calculate idle from last field [3]
long idle = curTicks[3] - prevTicks[3];
// Copy latest ticks to earlier position for next call
if (update) {
System.arraycopy(curTicks, 0, prevTicks, 0, curTicks.length);
}
// return
if (total > 0 && idle >= 0) {
return (double) (total - idle) / total;
}
return 0d;
}
/**
* {@inheritDoc}
*/
@Override
public long[] getSystemCpuLoadTicks() {
updateSystemTicks();
// Make a copy
long[] ticks = new long[curTicks.length];
System.arraycopy(curTicks, 0, ticks, 0, curTicks.length);
return ticks;
}
/**
* Updates system tick information from parsing /proc/stat. Array with four
* elements representing clock ticks or milliseconds (platform dependent)
* spent in User (0), Nice (1), System (2), and Idle (3) states. By
* measuring the difference between ticks across a time interval, CPU load
* over that interval may be calculated.
*
* @return An array of 4 long values representing time spent in User,
* Nice(if applicable), System, and Idle states.
*/
private static void updateSystemTicks() {
// /proc/stat expected format
// first line is overall user,nice,system,idle, etc.
// cpu 3357 0 4313 1362393 ...
String tickStr = "";
try {
List<String> procStat = FileUtil.readFile("/proc/stat");
if (!procStat.isEmpty())
tickStr = procStat.get(0);
} catch (IOException e) {
System.err.println("Problem with: /proc/stat");
System.err.println(e.getMessage());
return;
}
String[] tickArr = tickStr.split("\\s+");
if (tickArr.length < 5)
return;
for (int i = 0; i < 4; i++) {
curTicks[i] = Long.parseLong(tickArr[i + 1]);
}
}
/**
* {@inheritDoc}
*/
@Override
public double getSystemCpuLoad() {
if (sunMXBean) {
return ((com.sun.management.OperatingSystemMXBean) OS_MXBEAN)
.getSystemCpuLoad();
}
return getSystemCpuLoadBetweenTicks();
}
/**
* {@inheritDoc}
*/
@Override
public double getSystemLoadAverage() {
return OS_MXBEAN.getSystemLoadAverage();
}
/**
* {@inheritDoc}
*/
@Override
public double getProcessorCpuLoadBetweenTicks() {
// Check if > ~ 0.95 seconds since last tick count.
long now = System.currentTimeMillis();
if (now - procTickTime > 950) {
// Enough time has elapsed. Update array in place
updateProcessorTicks();
// Copy arrays in place
System.arraycopy(curProcTicks, 0, prevProcTicks, 0,
curProcTicks.length);
System.arraycopy(allProcessorTicks[processorNumber], 0,
curProcTicks, 0, curProcTicks.length);
procTickTime = now;
}
long total = 0;
for (int i = 0; i < curProcTicks.length; i++) {
total += (curProcTicks[i] - prevProcTicks[i]);
}
// Calculate idle from last field [3]
long idle = curProcTicks[3] - prevProcTicks[3];
// update
return (total > 0 && idle >= 0) ? (double) (total - idle) / total : 0d;
}
/**
* {@inheritDoc}
*/
public long[] getProcessorCpuLoadTicks() {
updateProcessorTicks();
return allProcessorTicks[processorNumber];
}
/**
* Updates the tick array for all processors if more than 100ms has elapsed
* since the last update. This permits using the allProcessorTicks as a
* cache when iterating over processors so that the /proc/stat file is only
* read once
*/
private static void updateProcessorTicks() {
// Update no more frequently than 100ms so this is only triggered once
// during iteration over Processors
long now = System.currentTimeMillis();
if (now - allProcTickTime < 100)
return;
// /proc/stat expected format
// first line is overall user,nice,system,idle, etc.
// cpu 3357 0 4313 1362393 ...
// per-processor subsequent lines for cpu0, cpu1, etc.
try {
int cpu = 0;
List<String> procStat = FileUtil.readFile("/proc/stat");
for (String stat : procStat) {
if (stat.startsWith("cpu") && !stat.startsWith("cpu ")) {
String[] tickArr = stat.split("\\s+");
if (tickArr.length < 5)
break;
for (int i = 0; i < 4; i++) {
allProcessorTicks[cpu][i] = Long
.parseLong(tickArr[i + 1]);
}
if (++cpu >= numCPU)
break;
}
}
} catch (IOException e) {
System.err.println("Problem with: /proc/stat");
System.err.println(e.getMessage());
}
allProcTickTime = now;
}
@Override
public String toString() {
return getName();
}
}