[Satellite 5.7] - spacewalk-clone-by-date is too slow on Red Hat Satellite 5.7

Issue

• The spacewalk-clone-by-date command is too slow on Red Hat Satellite 5.7

# time spacewalk-clone-by-date --config=/channels.conf --to_date=2015-10-21 --use-update-date
Reading repository information.
Using update_date.

By continuing the following channels will be created:
test-redone-20151016-server-5-2
Cloning rhel-x86_64-server-5 to test-redone-20151016-server-5-2 with original package set.
Copying repodata, please wait.
Solving Dependencies (2830):
________________________________________
######################################## - complete
Processing Dependencies:
________________________________________
######################################## - complete

By continuing the following will be cloned:
  rhel-x86_64-server-5 -> test-redone-20151016-server-5-2  (3094/3095 Errata)
Cloning Errata into test-redone-20151016-server-5-2 (3094):
________________________________________
############################Traceback (most recent call last):
  File "/usr/bin/spacewalk-clone-by-date", line 411, in <module>
    sys.exit(abs(main() or 0))
  File "/usr/bin/spacewalk-clone-by-date", line 401, in main
    return cloneByDate.main(args)
  File "/usr/share/rhn/utils/cloneByDate.py", line 282, in main
    cloner.clone(options.skip_depsolve)
  File "/usr/share/rhn/utils/cloneByDate.py", line 464, in clone
    cloner.process()
  File "/usr/share/rhn/utils/cloneByDate.py", line 631, in process
    self.clone()
  File "/usr/share/rhn/utils/cloneByDate.py", line 724, in clone
    self.remote_api.clone_errata(self.to_label, errata_set)
  File "/usr/share/rhn/utils/cloneByDate.py", line 868, in clone_errata
    errata_list)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1199, in __call__
    return self.__send(self.__name, args)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1489, in __request
    verbose=self.__verbose
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1243, in request
    headers
xmlrpclib.ProtocolError: <ProtocolError for localhost/rpc/api: 503 Service Temporarily Unavailable>

real    448m10.395s
user    1m4.734s
sys     0m0.856s