7d0e5ebe69
This commit lets the object server use splice() and tee() to move data
from disk to the network without ever copying it into user space.
Requires Linux. Sorry, FreeBSD folks. You still have the old
mechanism, as does anyone who doesn't want to use splice. This
requires a relatively recent kernel (2.6.38+) to work, which includes
the two most recent Ubuntu LTS releases (Precise and Trusty) as well
as RHEL 7. However, it excludes Lucid and RHEL 6. On those systems,
setting "splice = on" will result in warnings in the logs but no
actual use of splice.
Note that this only applies to GET responses without Range headers. It
can easily be extended to single-range GET requests, but this commit
leaves that for future work. Same goes for PUT requests, or at least
non-chunked ones.
On some real hardware I had laying around (not a VM), this produced a
37% reduction in CPU usage for GETs made directly to the object
server. Measurements were done by looking at /proc/<pid>/stat,
specifically the utime and stime fields (user and kernel CPU jiffies,
respectively).
Note: There is a Python module called "splicetee" available on PyPi,
but it's licensed under the GPL, so it cannot easily be added to
OpenStack's requirements. That's why this patch uses ctypes instead.
Also fixed a long-standing annoyance in FakeLogger:
>>> fake_logger.warn('stuff')
>>> fake_logger.get_lines_for_level('warn')
[]
>>>
This, of course, is because the correct log level is 'warning'. Now
you get a KeyError if you call get_lines_for_level with a bogus log
level.
Change-Id: Ic6d6b833a5b04ca2019be94b1b90d941929d21c8
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| bin | ||
| doc | ||
| etc | ||
| examples | ||
| swift | ||
| test | ||
| .coveragerc | ||
| .functests | ||
| .gitignore | ||
| .gitreview | ||
| .mailmap | ||
| .probetests | ||
| .unittests | ||
| AUTHORS | ||
| babel.cfg | ||
| CHANGELOG | ||
| CONTRIBUTING.md | ||
| LICENSE | ||
| MANIFEST.in | ||
| README.md | ||
| requirements.txt | ||
| setup.cfg | ||
| setup.py | ||
| test-requirements.txt | ||
| tox.ini | ||
Swift
A distributed object storage system designed to scale from a single machine to thousands of servers. Swift is optimized for multi-tenancy and high concurrency. Swift is ideal for backups, web and mobile content, and any other unstructured data that can grow without bound.
Swift provides a simple, REST-based API fully documented at http://docs.openstack.org/.
Swift was originally developed as the basis for Rackspace's Cloud Files and was open-sourced in 2010 as part of the OpenStack project. It has since grown to include contributions from many companies and has spawned a thriving ecosystem of 3rd party tools. Swift's contributors are listed in the AUTHORS file.
Docs
To build documentation install sphinx (pip install sphinx), run
python setup.py build_sphinx, and then browse to /doc/build/html/index.html.
These docs are auto-generated after every commit and available online at
http://docs.openstack.org/developer/swift/.
For Developers
The best place to get started is the "SAIO - Swift All In One". This document will walk you through setting up a development cluster of Swift in a VM. The SAIO environment is ideal for running small-scale tests against swift and trying out new features and bug fixes.
You can run unit tests with .unittests and functional tests with
.functests.
Code Organization
- bin/: Executable scripts that are the processes run by the deployer
- doc/: Documentation
- etc/: Sample config files
- swift/: Core code
- account/: account server
- common/: code shared by different modules
- middleware/: "standard", officially-supported middleware
- ring/: code implementing Swift's ring
- container/: container server
- obj/: object server
- proxy/: proxy server
- test/: Unit and functional tests
Data Flow
Swift is a WSGI application and uses eventlet's WSGI server. After the
processes are running, the entry point for new requests is the Application
class in swift/proxy/server.py. From there, a controller is chosen, and the
request is processed. The proxy may choose to forward the request to a back-
end server. For example, the entry point for requests to the object server is
the ObjectController class in swift/obj/server.py.
For Deployers
Deployer docs are also available at http://docs.openstack.org/developer/swift/. A good starting point is at http://docs.openstack.org/developer/swift/deployment_guide.html
You can run functional tests against a swift cluster with .functests. These
functional tests require /etc/swift/test.conf to run. A sample config file
can be found in this source tree in test/sample.conf.
For Client Apps
For client applications, official Python language bindings are provided at http://github.com/openstack/python-swiftclient.
Complete API documentation at http://docs.openstack.org/api/openstack-object-storage/1.0/content/
For more information come hang out in #openstack-swift on freenode.
Thanks,
The Swift Development Team