bundle2: implement generic part payload decoder
The previous commit extracted _payloadchunks() to a new derived class.
There was still a reference to this method in unbundlepart, making
unbundlepart unusable on its own.
This commit implements a generic version of a bundle2 part payload
decoder, without offset tracking. seekableunbundlepart._payloadchunks()
has been refactored to consume it, adding offset tracking like before.
We also implement unbundlepart._payloadchunks(), which is a thin
wrapper for it. Since we never instantiate unbundlepart directly,
this new method is not used. This will be changed in subsequent
commits.
The new implementation also inlines some simple code from unpackermixin
and adds some local variable to prevent extra function calls and
attribute lookups. `hg perfbundleread` on an uncompressed Firefox
bundle seems to show a minor win:
! bundle2 iterparts()
! wall 12.593258 comb 12.250000 user 8.870000 sys 3.380000 (best of 3)
! wall 10.891305 comb 10.820000 user 7.990000 sys 2.830000 (best of 3)
! bundle2 part seek()
! wall 13.173163 comb 11.100000 user 8.390000 sys 2.710000 (best of 3)
! wall 12.991478 comb 10.390000 user 7.720000 sys 2.670000 (best of 3)
! bundle2 part read(8k)
! wall 9.483612 comb 9.480000 user 8.420000 sys 1.060000 (best of 3)
! wall 8.599892 comb 8.580000 user 7.720000 sys 0.860000 (best of 3)
! bundle2 part read(16k)
! wall 9.159815 comb 9.150000 user 8.220000 sys 0.930000 (best of 3)
! wall 8.265361 comb 8.250000 user 7.360000 sys 0.890000 (best of 3)
! bundle2 part read(32k)
! wall 9.141308 comb 9.130000 user 8.220000 sys 0.910000 (best of 3)
! wall 8.290308 comb 8.280000 user 7.330000 sys 0.950000 (best of 3)
! bundle2 part read(128k)
! wall 8.880587 comb 8.850000 user 7.960000 sys 0.890000 (best of 3)
! wall 8.204900 comb 8.150000 user 7.210000 sys 0.940000 (best of 3)
Function call overhead in Python strikes again!
Of course, bundle2 decoding CPU overhead is likely small compared to
decompression and changegroup application. But every little bit helps.
Differential Revision: https://phab.mercurial-scm.org/D1387
====
hg
====
---------------------------------------
Mercurial source code management system
---------------------------------------
:Author: Matt Mackall <mpm@selenic.com>
:Organization: Mercurial
:Manual section: 1
:Manual group: Mercurial Manual
.. contents::
:backlinks: top
:class: htmlonly
:depth: 1
Synopsis
""""""""
**hg** *command* [*option*]... [*argument*]...
Description
"""""""""""
The **hg** command provides a command line interface to the Mercurial
system.
Command Elements
""""""""""""""""
files...
indicates one or more filename or relative path filenames; see
`File Name Patterns`_ for information on pattern matching
path
indicates a path on the local machine
revision
indicates a changeset which can be specified as a changeset
revision number, a tag, or a unique substring of the changeset
hash value
repository path
either the pathname of a local repository or the URI of a remote
repository.
.. include:: hg.1.gendoc.txt
Files
"""""
``/etc/mercurial/hgrc``, ``$HOME/.hgrc``, ``.hg/hgrc``
This file contains defaults and configuration. Values in
``.hg/hgrc`` override those in ``$HOME/.hgrc``, and these override
settings made in the global ``/etc/mercurial/hgrc`` configuration.
See |hgrc(5)|_ for details of the contents and format of these
files.
``.hgignore``
This file contains regular expressions (one per line) that
describe file names that should be ignored by **hg**. For details,
see |hgignore(5)|_.
``.hgsub``
This file defines the locations of all subrepositories, and
tells where the subrepository checkouts came from. For details, see
:hg:`help subrepos`.
``.hgsubstate``
This file is where Mercurial stores all nested repository states. *NB: This
file should not be edited manually.*
``.hgtags``
This file contains changeset hash values and text tag names (one
of each separated by spaces) that correspond to tagged versions of
the repository contents. The file content is encoded using UTF-8.
``.hg/last-message.txt``
This file is used by :hg:`commit` to store a backup of the commit message
in case the commit fails.
``.hg/localtags``
This file can be used to define local tags which are not shared among
repositories. The file format is the same as for ``.hgtags``, but it is
encoded using the local system encoding.
Some commands (e.g. revert) produce backup files ending in ``.orig``,
if the ``.orig`` file already exists and is not tracked by Mercurial,
it will be overwritten.
Bugs
""""
Probably lots, please post them to the mailing list (see Resources_
below) when you find them.
See Also
""""""""
|hgignore(5)|_, |hgrc(5)|_
Author
""""""
Written by Matt Mackall <mpm@selenic.com>
Resources
"""""""""
Main Web Site: https://mercurial-scm.org/
Source code repository: https://www.mercurial-scm.org/repo/hg
Mailing list: https://www.mercurial-scm.org/mailman/listinfo/mercurial/
Copying
"""""""
Copyright (C) 2005-2017 Matt Mackall.
Free use of this software is granted under the terms of the GNU General
Public License version 2 or any later version.
.. include:: common.txt