How to prepare compiler_proxy?

Traceback (most recent call last):
File “goma_ctl.py”, line 3194, in
sys.exit(main())
File “goma_ctl.py”, line 3189, in main
goma.Dispatch(sys.argv[1:])
File “goma_ctl.py”, line 1434, in Dispatch
self._action_mappings.get(args[0], self._DefaultAction)()
File “goma_ctl.py”, line 808, in _EnsureStartCompilerProxy
self._GenericStartCompilerProxy(ensure=True, force_update=False)
File “goma_ctl.py”, line 767, in _GenericStartCompilerProxy
self._env.ExecCompilerProxy()
File “goma_ctl.py”, line 2117, in ExecCompilerProxy
return self._GetCompilerProxyPort(proc=proc) # set the new gomacc_port.
File “goma_ctl.py”, line 1677, in _GetCompilerProxyPort
raise e
main .Error: compiler_proxy is not ready? pid=9888