`Monitor cpu usage per thread in java?

Question

I would like to ask whether there is some simple way to determine cpu usage per thread in java. Thanks

Answer 1

I believe the JConsole (archived link) does provide this kind of information through a plugin

It uses ThreadMXBean getThreadCpuTime() function.

Something along the line of:

        long upTime = runtimeProxy.getUptime();         List<Long> threadCpuTime = new ArrayList<Long>();         for (int i = 0; i < threadIds.size(); i++) {             long threadId = threadIds.get(i);             if (threadId != -1) {                 threadCpuTime.add(threadProxy.getThreadCpuTime(threadId));             } else {                 threadCpuTime.add(0L);             }         }         int nCPUs = osProxy.getAvailableProcessors();         List<Float> cpuUsageList = new ArrayList<Float>();         if (prevUpTime > 0L && upTime > prevUpTime) {             // elapsedTime is in ms             long elapsedTime = upTime - prevUpTime;             for (int i = 0; i < threadIds.size(); i++) {                 // elapsedCpu is in ns                 long elapsedCpu = threadCpuTime.get(i) - prevThreadCpuTime.get(i);                 // cpuUsage could go higher than 100% because elapsedTime                 // and elapsedCpu are not fetched simultaneously. Limit to                 // 99% to avoid Chart showing a scale from 0% to 200%.                 float cpuUsage = Math.min(99F, elapsedCpu / (elapsedTime * 1000000F * nCPUs));                 cpuUsageList.add(cpuUsage);             }         }