/**
* Check if any threads are deadlocked. If any, print the thread dump for those threads.
*
* @return a deadlock message and the formatted thread dump of the deadlocked threads
*/
private static String findDeadlock() {
ThreadInfo[] tinfos = null;
long[] ids = threadMXBean.findDeadlockedThreads();
if (ids != null) {
tinfos = threadMXBean.getThreadInfo(threadMXBean.findDeadlockedThreads(), true, true);
if (tinfos != null) {
StringBuilder sb = new StringBuilder("Deadlock found between the following threads:");
sb.append(CRLF);
sb.append(getThreadDump(tinfos));
return sb.toString();
}
}
return "";
}
public ThreadInfo[] getDeadLocks() {
final long[] ids = _tmx.findDeadlockedThreads();
if (ids != null) {
return _tmx.getThreadInfo(ids, true, true);
} else {
return null;
}
}
// Return thread IDs of deadlocked threads or null if any.
// It finds deadlocks involving only monitors if it's a Tiger VM.
// Otherwise, it finds deadlocks involving both monitors and
// the concurrent locks.
public long[] findDeadlockedThreads() throws IOException {
ThreadMXBean tm = getThreadMXBean();
if (supportsLockUsage && tm.isSynchronizerUsageSupported()) {
return tm.findDeadlockedThreads();
} else {
return tm.findMonitorDeadlockedThreads();
}
}
private long[] findDeadlockedThreads(ThreadMXBean mbean) {
// JDK 1.5 only supports the findMonitorDeadlockedThreads()
// method, so you need to comment out the following three lines
if (mbean.isSynchronizerUsageSupported()) {
return mbean.findDeadlockedThreads();
}
return mbean.findMonitorDeadlockedThreads();
}
@Override
public void run() {
while (doRun) {
long[] threadIds = tmxb.findDeadlockedThreads();
try {
// ...
Thread.sleep(10000);
} catch (InterruptedException ex) {
Logger.getLogger(DeadLockDetector.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
/* (non-Javadoc)
* @see org.epics.pvaccess.server.plugins.BeaconServerStatusProvider#getServerStatusData()
*/
public PVField getServerStatusData() {
status
.getIntField("connections")
.put(context.getTransportRegistry().numberOfActiveTransports());
status.getLongField("allocatedMemory").put(Runtime.getRuntime().totalMemory());
status.getLongField("freeMemory").put(Runtime.getRuntime().freeMemory());
ThreadMXBean threadMBean = ManagementFactory.getThreadMXBean();
status.getIntField("threads").put(threadMBean.getThreadCount());
final long[] deadlocks =
threadMBean.isSynchronizerUsageSupported()
? threadMBean.findDeadlockedThreads()
: threadMBean.findMonitorDeadlockedThreads();
status.getIntField("deadlocks").put((deadlocks != null) ? deadlocks.length : 0);
OperatingSystemMXBean osMBean = ManagementFactory.getOperatingSystemMXBean();
status.getDoubleField("averageSystemLoad").put(osMBean.getSystemLoadAverage());
return status;
}
@Override
public void run() {
boolean dead = false;
while (!dead && !interrupted()) {
try {
Thread.sleep(10000);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
dead = true;
}
ThreadMXBean tmx = ManagementFactory.getThreadMXBean();
long[] ids = tmx.findDeadlockedThreads();
if (ids != null) {
Spout.getLogger().info("Checking for deadlocks");
ThreadInfo[] infos = tmx.getThreadInfo(ids, true, true);
Spout.getLogger().severe("The following threads are deadlocked:");
for (ThreadInfo ti : infos) {
Spout.getLogger().severe(ti.toString());
}
}
}
}
@RequestMapping("/deadlockCheck")
@ResponseBody
public JSONObject doDeadlockCheck(HttpServletRequest request) {
try {
String app = request.getParameter("app");
ThreadMXBean tBean = JMConnManager.getThreadMBean(app);
JSONObject json = new JSONObject();
long[] dTh = tBean.findDeadlockedThreads();
if (dTh != null) {
ThreadInfo[] threadInfo = tBean.getThreadInfo(dTh, Integer.MAX_VALUE);
StringBuffer sb = new StringBuffer();
for (ThreadInfo info : threadInfo) {
sb.append("\n").append(info);
}
json.put("hasdeadlock", true);
json.put("info", sb);
return json;
}
json.put("hasdeadlock", false);
return json;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public long[] findDeadlockedThreads() {
ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
return threadMXBean.findDeadlockedThreads();
}