An unknown error has occured in the Java remote_api handler for this call

Question

I'm trying to use bulkloader to load entities to my GAE app, which is already hosted on GAE. I'm not using DEV server now. It was all fine couple of weeks ago, when I left the app, now after like 2 or 3 updates of GoogleAppEngineLauncher to 1.9 I can't use same commands as before to load entities, because it ends with tons of errors:

[INFO    ] Connecting to my-app.appspot.com/remote_api
Traceback (most recent call last):
  File "/usr/local/bin/appcfg.py", line 126, in <module>
    run_file(__file__, globals())
  File "/usr/local/bin/appcfg.py", line 122, in run_file
    execfile(_PATHS.script_file(script_name), globals_)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 4934, in <module>
    main(sys.argv)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 4925, in main
    result = AppCfgApp(argv).Run()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 2648, in Run
    self.action(self)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 4605, in __call__
    return method()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 4417, in PerformUpload
    run_fn(args)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/appcfg.py", line 4298, in RunBulkloader
    sys.exit(bulkloader.Run(arg_dict))
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/bulkloader.py", line 4408, in Run
    return _PerformBulkload(arg_dict)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/bulkloader.py", line 4273, in _PerformBulkload
    loader.finalize()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/ext/bulkload/bulkloader_config.py", line 382, in finalize
    self.reserve_keys(self.keys_to_reserve)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/bulkloader.py", line 1217, in ReserveKeys
    datastore._GetConnection()._reserve_keys(ConvertKeys(keys))
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/datastore/datastore_rpc.py", line 2108, in _reserve_keys
    self._async_reserve_keys(None, keys).get_result()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/datastore/datastore_rpc.py", line 890, in get_result
    results = self.__rpcs[0].get_result()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/api/apiproxy_stub_map.py", line 612, in get_result
    return self.__get_result_hook(self)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/datastore/datastore_rpc.py", line 2151, in __reserve_keys_hook
    self.check_rpc_success(rpc)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/datastore/datastore_rpc.py", line 1331, in check_rpc_success
    rpc.check_success()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/api/apiproxy_stub_map.py", line 578, in check_success
    self.__rpc.CheckSuccess()
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/api/apiproxy_rpc.py", line 156, in _WaitImpl
    self.request, self.response)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/ext/remote_api/remote_api_stub.py", line 200, in MakeSyncCall
    self._MakeRealSyncCall(service, call, request, response)
  File "/Applications/ADT/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/ext/remote_api/remote_api_stub.py", line 236, in _MakeRealSyncCall
    raise UnknownJavaServerError("An unknown error has occured in the "
google.appengine.ext.remote_api.remote_api_stub.UnknownJavaServerError: An unknown error has occured in the Java remote_api handler for this call.

AppEngine is written in JAVA, however I use python sdk to use bulkloader.

Answer 1

Same day I used Datastore Admin to wipe app database. This uses much quotas, and this is why upload was failing (just guessing). Still it's weird since my project has billing enabled.