Jstack Profiler

Simple profiler that takes concatenation of jstack's output as input. It's useful, when you want to find out what's going on a production server that you can't stop or profile (with classic profiler).

How to compile

$ sbt assembly

It generates a big jar file in the target directory

How to use

First generate a full thread dump output every n seconds (60 sec in this example), append those thread dumps in a file (jstack.log in this example). Ctrl+C to terminate

$ while true ; do jstack PID >> jstack.log ; sleep 60 ; done

Then launch the analyze with:

$ cat jstack.log > java -jar target/jstack-profiler-assembly-0.1.jar

Here is an example of the output:

Runnable methods breakout
-------------------------
rank    time    name
0       82.50%  java.lang.Thread.run(Thread.java:722)
1       80.00%  sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)
2       11.79%  org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
3       11.43%  sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:69)
4       2.86%   org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
5       2.50%   sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:228)
6       1.79%   org.springframework.jdbc.core.JdbcTemplate$3.doInPreparedStatement(JdbcTemplate.java:844)
7       0.71%   java.net.SocketInputStream.socketRead0(Native Method)
8       0.36%   com.google.gson.stream.JsonWriter.string(JsonWriter.java:535)

Blocked/Waiting methods breakout
--------------------------------
rank    time    name
0       41.96%  com.example.service.run(Servie.java:123)
1       24.22%  sun.misc.Unsafe.park(Native Method)
2       12.61%  java.lang.Thread.run(Thread.java:722)
3       11.83%  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1043)
4       10.27%  java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:226)
5       5.80%   java.util.concurrent.LinkedBlockingDeque.takeFirst(LinkedBlockingDeque.java:440)
6       4.13%   com.google.common.cache.LocalCache.get(LocalCache.java:3980)
7       2.68%   com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:534)
8       1.56%   java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:807)
9       1.45%   java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
10      1.34%   java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(SynchronousQueue.java:424)
11      0.78%   com.google.common.cache.LocalCache$Segment.waitForLoadingValue(LocalCache.java:2333)
12      0.11%   java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)