Page History

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• Impalad - debug port is 30000 + x , where x is the running number of impalads started. If 3 daemons are started, the ports range from 3000[0-2].
• Catalogd - debug port is 30000 + x, where x is the size of the cluster. If 3 daemons are started the debug port is 3000330030.

As soon as the JVM is started, it is possible to connect using the above ports. The simplest debugger is jdb:

jdb -attach localhost:3000030030

Using Eclipse to attach to a running Impalad JVM

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define hook-stop
  handle SIGSEGV stop print pass
end
define hook-run
  handle SIGSEGV nostop noprint pass
end
define hook-continue
  handle SIGSEGV nostop noprint pass
end

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The follow bash function is useful for getting the stack traces of all the threads (there are usually plenty of them).

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