# -*- coding: utf-8 -*-
# Copyright 2015 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Additional help text for throttling gsutil."""
from __future__ import absolute_import
from gslib.help_provider import HelpProvider
_DETAILED_HELP_TEXT = ("""
OVERVIEW
Particularly when used with the -m (multi-threading) option, gsutil can
consume a significant amount of network bandwidth. In some cases this can
cause problems, for example if you start a large rsync operation over a
network link that's also used by a number of other important jobs.
While gsutil has no built-in support for throttling requests, there are
various tools available on Linux and MacOS that can be used to throttle
gsutil requests.
One tool is `trickle`_
(available via apt-get on Ubuntu systems), which will let you limit how much
bandwidth gsutil consumes. For example, the following command would limit
upload and download bandwidth consumed by gsutil rsync to 100 KBps:
trickle -d 100 -u 100 gsutil -m rsync -r ./dir gs://some bucket
Another tool is
`ionice`_ (built
in to many Linux systems), which will let you limit how much I/O capacity
gsutil consumes (e.g., to avoid letting it monopolize your local disk). For
example, the following command would reduce I/O priority of gsutil so it
doesn't monopolize your local disk:
ionice -c 2 -n 7 gsutil -m rsync -r ./dir gs://some bucket
""")
class CommandOptions(HelpProvider):
"""Additional help text for throttling gsutil."""
# Help specification. See help_provider.py for documentation.
help_spec = HelpProvider.HelpSpec(
help_name='throttling',
help_name_aliases=['bandwidth', 'limit', 'nice'],
help_type='additional_help',
help_one_line_summary='Throttling gsutil',
help_text=_DETAILED_HELP_TEXT,
subcommand_help_text={},
)