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Page Comparison - Troubleshooting in Production Environments (v.3 vs v.4) - Clustering Guide 4.2.0 - WSO2 Documentation

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  1. Find the thread ID (the one that belongs to the corresponding PID) that takes up the highest CPU usage by examining the thread-usage.txt file.

    Code Block
    %CPU CPU  NI S     TIME   PID   TID
      0.0   -   0 S 00:00:00  1519  1602
      0.0   -   0 S 00:00:00  1519  1603
     24.8   -   0 R 00:06:19  1519  1604
      2.4   -   0 S 00:00:37  1519  1605
      0.0   -   0 S 00:00:00  1519  1606

    In this example, the thread ID that takes up the highest CPU usage is 1604.

  2. Convert the decimal value (in this case 1604) to hexadecimal. You can use an online converter to do this. The hexadecimal value for 1604 is 644.
  3. Search the thread-dump.txt file for the hexadecimal obtained in order to identify the thread that spins. In this case, the hexadecimal value to search for is 644. The thread-dump.txt file should have that value as a thread ID of one thread.
  4. That thread usually has a stack trace, and that's the lead you need to find the issue. In this example, the stack trace of the thread that spins is as follows.

    Code Block
    "HTTPS-Sender I/O dispatcher-1" prio=10 tid=0x00007fb54c010000 nid=0x644 runnable [0x00007fb534e20000]
       java.lang.Thread.State: RUNNABLE
            at org.apache.http.impl.nio.reactor.IOSessionImpl.getEventMask(
            - locked <0x00000006cd91fef8> (a org.apache.http.impl.nio.reactor.IOSessionImpl)
            at org.apache.http.nio.reactor.ssl.SSLIOSession.updateEventMask(
            at org.apache.http.nio.reactor.ssl.SSLIOSession.inboundTransport(
            - locked <0x00000006cd471df8> (a org.apache.http.nio.reactor.ssl.SSLIOSession)
            at org.apache.http.impl.nio.reactor.AbstractIODispatch.inputReady(
            at org.apache.http.impl.nio.reactor.BaseIOReactor.readable(
            at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvent(
            at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvents(
            at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(
            at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(
            at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$