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Move other improvements and optimization sections above deprecated. 

This arrangement means the sections that have summaries come
first, and everything else comes after those.
This commit is contained in:
R David Murray 2013-12-23 21:23:36 -05:00
parent 4d48f2a6e7
commit bcaaecfe1e
1 changed files with 43 additions and 42 deletions
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Doc/whatsnew/3.4.rst
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@ -937,48 +937,6 @@ Add a filter function to ignore some packages (tests for instance),
(Contributed by Christian Tismer in :issue:`19274`.) (Contributed by Christian Tismer in :issue:`19274`.)
Other improvements
==================
* Tab-completion is now enabled by default in the interactive interpreter.
(Contributed by Antoine Pitrou and Éric Araujo in :issue:`5845`.)
* Invoking the Python interpreter with ``--version`` now outputs the version to
standard output instead of standard error (:issue:`18338`). Similar changes
were made to :mod:`argparse` (:issue:`18920`) and other modules that have
script-like invocation capabilities (:issue:`18922`).
Optimizations
=============
Major performance enhancements have been added:
* The UTF-32 decoder is now 3x to 4x faster.
* The cost of hash collisions for sets is now reduced. Each hash table
probe now checks a series of consecutive, adjacent key/hash pairs before
continuing to make random probes through the hash table. This exploits
cache locality to make collision resolution less expensive.
The collision resolution scheme can be described as a hybrid of linear
probing and open addressing. The number of additional linear probes
defaults to nine. This can be changed at compile-time by defining
LINEAR_PROBES to be any value. Set LINEAR_PROBES=0 to turn-off
linear probing entirely.
(Contributed by Raymond Hettinger in :issue:`18771`.)
* The interpreter starts about 30% faster. A couple of measures lead to the
speedup. The interpreter loads fewer modules on startup, e.g. the :mod:`re`,
:mod:`collections` and :mod:`locale` modules and their dependencies are no
longer imported by default. The marshal module has been improved to load
compiled Python code faster.
(Contributed by Antoine Pitrou, Christian Heimes and Victor Stinner in
:issue:`19219`, :issue:`19218`, :issue:`19209`, :issue:`19205` and
:issue:`9548`)
CPython Implementation Changes CPython Implementation Changes
============================== ==============================
@ -1067,6 +1025,49 @@ Changes to Python's build process and to the C API include:
be made available as a public API for third party use in Python 3.4. be made available as a public API for third party use in Python 3.4.
Other improvements
==================
* Tab-completion is now enabled by default in the interactive interpreter.
(Contributed by Antoine Pitrou and Éric Araujo in :issue:`5845`.)
* Invoking the Python interpreter with ``--version`` now outputs the version to
standard output instead of standard error (:issue:`18338`). Similar changes
were made to :mod:`argparse` (:issue:`18920`) and other modules that have
script-like invocation capabilities (:issue:`18922`).
Optimizations
=============
Major performance enhancements have been added:
* The UTF-32 decoder is now 3x to 4x faster.
* The cost of hash collisions for sets is now reduced. Each hash table
probe now checks a series of consecutive, adjacent key/hash pairs before
continuing to make random probes through the hash table. This exploits
cache locality to make collision resolution less expensive.
The collision resolution scheme can be described as a hybrid of linear
probing and open addressing. The number of additional linear probes
defaults to nine. This can be changed at compile-time by defining
LINEAR_PROBES to be any value. Set LINEAR_PROBES=0 to turn-off
linear probing entirely.
(Contributed by Raymond Hettinger in :issue:`18771`.)
* The interpreter starts about 30% faster. A couple of measures lead to the
speedup. The interpreter loads fewer modules on startup, e.g. the :mod:`re`,
:mod:`collections` and :mod:`locale` modules and their dependencies are no
longer imported by default. The marshal module has been improved to load
compiled Python code faster.
(Contributed by Antoine Pitrou, Christian Heimes and Victor Stinner in
:issue:`19219`, :issue:`19218`, :issue:`19209`, :issue:`19205` and
:issue:`9548`)
Deprecated Deprecated
========== ==========