OpenStack Storage (Swift)
Go to file
Alistair Coles bbaed18e9b diskfile: don't remove recently written non-durables
DiskFileManager will remove any stale files during
cleanup_ondisk_files(): these include tombstones and nondurable EC
data fragments whose timestamps are older than reclaim_age. It can
usually be safely assumed that a non-durable data fragment older than
reclaim_age is not going to become durable. However, if an agent PUTs
objects with specified older X-Timestamps (for example the reconciler
or container-sync) then there is a window of time during which the
object server has written an old non-durable data file but has not yet
committed it to make it durable.

Previously, if another process (for example the reconstructor) called
cleanup_ondisk_files during this window then the non-durable data file
would be removed. The subsequent attempt to commit the data file would
then result in a traceback due to there no longer being a data file to
rename, and of course the data file is lost.

This patch modifies cleanup_ondisk_files to not remove old, otherwise
stale, non-durable data files that were only written to disk in the
preceding 'commit_window' seconds. 'commit_window' is configurable for
the object server and defaults to 60.0 seconds.

Closes-Bug: #1936508
Related-Change: I0d519ebaaade35249fb7b17bd5f419ffdaa616c0
Change-Id: I5f3318a44af64b77a63713e6ff8d0fd3b6144f13
2021-07-19 21:18:02 +01:00
api-ref/source Switch to newer openstackdocstheme and reno versions 2020-06-03 08:31:04 +02:00
bin recon: refactor common recon names into a common location 2021-06-29 15:22:57 -07:00
doc diskfile: don't remove recently written non-durables 2021-07-19 21:18:02 +01:00
docker Merge "Switch IRC references from freenode to OFTC" 2021-06-02 10:52:08 +00:00
etc diskfile: don't remove recently written non-durables 2021-07-19 21:18:02 +01:00
examples Update SAIO & docker image to use 62xx ports 2020-07-20 15:17:12 -07:00
releasenotes Update master for stable/wallaby 2021-03-22 11:10:31 -07:00
roles Merge "dsvm: Use devstack's s3api "service"" 2020-06-07 18:58:39 +00:00
swift diskfile: don't remove recently written non-durables 2021-07-19 21:18:02 +01:00
test diskfile: don't remove recently written non-durables 2021-07-19 21:18:02 +01:00
tools Update some constraints for py2 2021-04-06 11:33:44 -07:00
.alltests tests: Stop invoking python just to get the real source directory 2019-10-15 15:08:42 -07:00
.coveragerc Show missing branches in coverage report. 2017-12-14 14:57:48 -08:00
.dockerignore Add Dockerfile to build a SAIO container image 2019-05-07 15:44:00 -04:00
.functests Give functional tests another chance to pass 2021-03-26 10:13:19 -07:00
.gitignore Give unit tests a second chance to pass 2020-12-04 22:21:58 -08:00
.gitreview OpenDev Migration Patch 2019-04-19 19:28:47 +00:00
.mailmap Use a less bogus credit for Melissa Ma Lei 2021-05-31 22:03:08 -07:00
.manpages Script for checking sanity of manpages 2016-02-10 14:16:56 -08:00
.probetests tests: Stop invoking python just to get the real source directory 2019-10-15 15:08:42 -07:00
.stestr.conf Give functional tests another chance to pass 2021-03-26 10:13:19 -07:00
.unittests tests: Stop invoking python just to get the real source directory 2019-10-15 15:08:42 -07:00
.zuul.yaml Merge "Run in-process func tests under py38" 2021-06-17 01:39:29 +00:00
AUTHORS Merge "Switch IRC references from freenode to OFTC" 2021-06-02 10:52:08 +00:00
bandit.yaml replace md5 with swift utils version 2020-12-15 09:52:55 -05:00
bindep.txt Add py3 probe tests on CentOS 8 2020-12-17 11:25:42 -08:00
CHANGELOG AUTHORS/CHANGELOG for 2.27.0 2021-03-16 08:58:32 -07:00
CONTRIBUTING.rst Switch IRC references from freenode to OFTC 2021-06-01 08:13:56 -07:00
Dockerfile Add Dockerfile to build a py3 swift docker image 2019-08-19 22:31:41 +02:00
Dockerfile-py3 Add Dockerfile to build a py3 swift docker image 2019-08-19 22:31:41 +02:00
LICENSE Convert LICENSE to use unix style line endings. 2012-12-19 12:48:27 -05:00
lower-constraints.txt Update some constraints for py2 2021-04-06 11:33:44 -07:00
MANIFEST.in Include s3api schemas in sdists 2018-07-11 16:56:28 -07:00
py2-constraints.txt Update some constraints for py2 2021-04-06 11:33:44 -07:00
README.rst Switch IRC references from freenode to OFTC 2021-06-01 08:13:56 -07:00
requirements.txt Remove <py3.5 dependencies from requirements.txt 2020-06-03 08:30:43 +02:00
REVIEW_GUIDELINES.rst Ussuri contrib docs community goal 2020-05-26 15:06:02 -07:00
setup.cfg Merge "Remove babel.cfg" 2021-06-09 21:45:41 +00:00
setup.py taking the global reqs that we can 2014-05-21 09:37:22 -07:00
test-requirements.txt Remove test-requirement on fixtures 2021-05-05 15:45:33 -07:00
tox.ini Run flake8 on bin/ files 2021-02-01 13:26:53 -08:00

OpenStack Swift

image

OpenStack Swift is 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 https://docs.openstack.org/swift/latest/.

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 run:

pip install -r requirements.txt -r doc/requirements.txt
sphinx-build -W -b html doc/source doc/build/html

and then browse to doc/build/html/index.html. These docs are auto-generated after every commit and available online at https://docs.openstack.org/swift/latest/.

For Developers

Getting Started

Swift is part of OpenStack and follows the code contribution, review, and testing processes common to all OpenStack projects.

If you would like to start contributing, check out these notes to help you get started.

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.

Tests

There are three types of tests included in Swift's source tree.

  1. Unit tests
  2. Functional tests
  3. Probe tests

Unit tests check that small sections of the code behave properly. For example, a unit test may test a single function to ensure that various input gives the expected output. This validates that the code is correct and regressions are not introduced.

Functional tests check that the client API is working as expected. These can be run against any endpoint claiming to support the Swift API (although some tests require multiple accounts with different privilege levels). These are "black box" tests that ensure that client apps written against Swift will continue to work.

Probe tests are "white box" tests that validate the internal workings of a Swift cluster. They are written to work against the "SAIO - Swift All In One" dev environment. For example, a probe test may create an object, delete one replica, and ensure that the background consistency processes find and correct the error.

You can run unit tests with .unittests, functional tests with .functests, and probe tests with .probetests. There is an additional .alltests script that wraps the other three.

To fully run the tests, the target environment must use a filesystem that supports large xattrs. XFS is strongly recommended. For unit tests and in-process functional tests, either mount /tmp with XFS or provide another XFS filesystem via the TMPDIR environment variable. Without this setting, tests should still pass, but a very large number will be skipped.

Code Organization

  • bin/: Executable scripts that are the processes run by the deployer
  • doc/: Documentation
  • etc/: Sample config files
  • examples/: Config snippets used in the docs
  • swift/: Core code
    • account/: account server
    • cli/: code that backs some of the CLI tools in bin/
    • common/: code shared by different modules
      • middleware/: "standard", officially-supported middleware
      • ring/: code implementing Swift's ring
    • container/: container server
    • locale/: internationalization (translation) data
    • obj/: object server
    • proxy/: proxy server
  • test/: Unit, functional, and probe 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 https://docs.openstack.org/swift/latest/. A good starting point is at https://docs.openstack.org/swift/latest/deployment_guide.html There is an ops runbook that gives information about how to diagnose and troubleshoot common issues when running a Swift cluster.

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 https://github.com/openstack/python-swiftclient.

Complete API documentation at https://docs.openstack.org/api-ref/object-store/

There is a large ecosystem of applications and libraries that support and work with OpenStack Swift. Several are listed on the associated projects page.


For more information come hang out in #openstack-swift on OFTC.

Thanks,

The Swift Development Team