/**
* get current process cpu usage data.
*
* @param pid process id
* @return ProcessUsage
*/
private ProcessUsage currentProcessUsage(final long pid) {
String file = getProcessStatFile(pid);
try {
String cpuline = FileUtils.file2string(file);
return new ProcessUsage(cpuline);
} catch (IOException ioe) {
System.err.println("cannot find stat of process: " + pid);
System.exit(1);
return null;
}
}
/**
* get current thread cpu usage data.
*
* @param pid process id
* @param tid thread id
* @return ThreadUsage
*/
private ThreadUsage currentThreadUsage(final long pid, final long tid) {
String file = getThreadStatFile(pid, tid);
try {
String cpuline = FileUtils.file2string(file);
return new ThreadUsage(cpuline);
} catch (IOException ioe) {
System.err.println(String.format("cannot find stat of process: %d, thread: %d", pid, tid));
System.exit(1);
return null;
}
}
/**
* read /proc/cpuinfo to get cpu numbers.
*
* @return cpu number
*/
public static int numCpus() {
List<String> cpuline_list = null;
try {
cpuline_list = FileUtils.grepFile(CPU_NUM_PATTERN, CPU_INFO_FILE);
} catch (IOException ioe) {
System.err.println("cannot find stat file: " + CPU_STAT_FILE);
System.exit(1);
return 0;
}
if (cpuline_list != null) {
return cpuline_list.size();
}
return 0;
}
/**
* get current cpu usage data.
*
* @return CPUUsage
*/
private CPUUsage currentCPUUsage() {
List<String> cpuline_list = null;
try {
cpuline_list = FileUtils.grepFile(CPU_JIFFIES_PATTERN, CPU_STAT_FILE);
} catch (IOException ioe) {
System.err.println("cannot find stat file: " + CPU_STAT_FILE);
System.exit(1);
return null;
}
if (cpuline_list != null && !cpuline_list.isEmpty()) {
return new CPUUsage(cpuline_list.get(0));
}
return null;
}
/**
* read /proc/cpuinfo to get cpu frequency in hz.
*
* @return cpu frequency in hz
*/
public static long cpuFrequencyInHz() {
List<String> cpuline_list = null;
try {
cpuline_list = FileUtils.grepFile(CPU_FREQ_PATTERN, CPU_INFO_FILE);
} catch (IOException ioe) {
System.err.println("cannot find stat file: " + CPU_STAT_FILE);
System.exit(1);
return 0;
}
if (cpuline_list != null && !cpuline_list.isEmpty()) {
String freqstr = cpuline_list.get(0);
int len = freqstr.length();
BigDecimal freq = new BigDecimal(freqstr.substring(0, len - 3));
long multiplier = getMultipiler(freqstr.charAt(len - 3));
return freq.multiply(new BigDecimal(Long.toString(multiplier))).longValue();
}
return 0;
}