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Contributing to the performance drive
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=====================================
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There is plenty of code to write. Testers are always welcome for experimental
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changes. In general, from the `Performance Tasks`_ graph, pick a BLUE node that has nothing
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pointing at it that is also BLUE, and start working on that.
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Ad-hoc performance work can also be done. One useful tool is the 'evil' debug
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flag. For instance running ``bzr -Devil commit -m "test"`` will log a backtrace
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to the bzr log file for every method call which triggers a slow or non-scalable
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part of the bzr library. So checking that a given command with ``-Devil`` has
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no backtraces logged to the log file is a good way to find problem function
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calls that might be nested deep in the code base.
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The performance drive is well under way. At the moment we are finalising the
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analysis documents from the sprint at London. If you were not at that sprint,
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please read the analysis documents - consider them living documents much like
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code, to be patched and corrected.
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If you were at the London performance sprint, please help finish documenting
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the core command analysis work. The core commands that have not been analysed
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are listed in `Performance Tasks`_ as the BLUE nodes. For quick reference:
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Once a given command has had its analysis created, the bottleneck of 'folk who
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attended London' is removed. The next task is in general the creation of a
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targeted API stack for that command. This API stack is done by starting with
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the cmd object in ``builtins.py`` and cleaning up the code so that the API used
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there is one which allows an implementation matching the analysis document.
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This then gets repeated, iteratively, on each of the called API's, until all
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the current slow code is cleanly abstracted behind the ``Tree``, ``Branch`` and
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The usual resources for contributing to bzr - the mailing list, wiki, bug
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tracker and IRC channels are documented in the `Bazaar Developer Guide`_. Additionally
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there are members of the project focusing on performance at the moment who are
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willing to mentor contributors on performance issues. Just send a mail to the
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list asking for mentoring on the step of the performance plan you want to help
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.. _`Bazaar Developer Guide`: ../en/developer-guide/HACKING.html
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.. _`Performance Tasks`: performance.png