def _get_host_assignments(self, current_hosts):
# Adjust the host assignments to account for added / removed hosts
host_list = [hosts.HostInfo(host, current_hosts.get_slots(host))
for host in current_hosts.host_assignment_order]
host_assignments_list = hosts.get_host_assignments(host_list, self._min_np, self._max_np)
host_assignments = defaultdict(list)
for slot_info in host_assignments_list:
host_assignments[slot_info.hostname].append(slot_info)
return host_assignments, host_assignments_list
def launch_gloo(command, exec_command, settings, nics, env, server_ip):
"""
Launches the given command multiple times using gloo.
Each command is launched via exec_command.
:param command: command to launch
:param exec_command: means to execute a single command
:param settings: settings for the distribution
:param nics: common interfaces
:param env: environment to use
:param server_ip: ip to use for rendezvous server
"""
# Make the output directory if it does not exist
if settings.output_filename:
_mkdir_p(settings.output_filename)
# start global rendezvous server and get port that it is listening on
rendezvous = RendezvousServer(settings.verbose)
# allocate processes into slots
hosts = parse_hosts(settings.hosts)
host_alloc_plan = get_host_assignments(hosts, settings.num_proc)
# start global rendezvous server and get port that it is listening on
global_rendezv_port = rendezvous.start_server()
rendezvous.httpd.init(host_alloc_plan)
run_command = get_run_command(command, server_ip, nics,
global_rendezv_port)
slot_info_to_command = _slot_info_to_command_fn(run_command, env)
event = register_shutdown_event()
args_list = [[slot_info_to_command(slot_info), slot_info, [event]]
for slot_info in host_alloc_plan]
# If an error occurs in one thread, entire process will be terminated.
# Otherwise, threads will keep running.
res = threads.execute_function_multithreaded(exec_command,
args_list,
block_until_all_done=True)
for name, value in sorted(res.items(), key=lambda item: item[1][1]):
exit_code, timestamp = value
if exit_code != 0:
raise RuntimeError(
'Horovod detected that one or more processes exited with non-zero '
'status, thus causing the job to be terminated. The first process '
'to do so was:\nProcess name: {name}\nExit code: {code}\n'.
format(name=name, code=exit_code))