Mercurial > hg
view hgext/purge.py @ 47120:7109a38830c9
dirstate-tree: Fold "tracked descendants" counter update in main walk
For the purpose of implementing `has_tracked_dir` (which means "has tracked
descendants) without an expensive sub-tree traversal, we maintaing a counter
of tracked descendants on each "directory" node of the tree-shaped dirstate.
Before this changeset, mutating or inserting a node at a given path would
involve:
* Walking the tree from root through ancestors to find the node or the spot
where to insert it
* Looking at the previous node if any to decide what counter update is needed
* Performing any node mutation
* Walking the tree *again* to update counters in ancestor nodes
When profiling `hg status` on a large repo, this second walk takes times
while loading a the dirstate from disk.
It turns out we have enough information to decide before he first tree walk
what counter update is needed. This changeset merges the two walks, gaining
~10% of the total time for `hg update` (in the same hyperfine benchmark as
the previous changeset).
---
Profiling was done by compiling with this `.cargo/config`:
[profile.release]
debug = true
then running with:
py-spy record -r 500 -n -o /tmp/hg.json --format speedscope -- \
./hg status -R $REPO --config experimental.dirstate-tree.in-memory=1
then visualizing the recorded JSON file in https://www.speedscope.app/
Differential Revision: https://phab.mercurial-scm.org/D10554
author | Simon Sapin <simon.sapin@octobus.net> |
---|---|
date | Fri, 30 Apr 2021 14:22:14 +0200 |
parents | bb3a5c0df06b |
children | 75d4e60c7c81 |
line wrap: on
line source
# Copyright (C) 2006 - Marco Barisione <marco@barisione.org> # # This is a small extension for Mercurial (https://mercurial-scm.org/) # that removes files not known to mercurial # # This program was inspired by the "cvspurge" script contained in CVS # utilities (http://www.red-bean.com/cvsutils/). # # For help on the usage of "hg purge" use: # hg help purge # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, see <http://www.gnu.org/licenses/>. '''command to delete untracked files from the working directory (DEPRECATED) The functionality of this extension has been included in core Mercurial since version 5.7. Please use :hg:`purge ...` instead. :hg:`purge --confirm` is now the default, unless the extension is enabled for backward compatibility. ''' # This empty extension looks pointless, but core mercurial checks if it's loaded # to implement the slightly different behavior documented above.