Mercurial > hg
view tests/test-lock-badness.t @ 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 | f44b9c72f061 |
children | adecb1ab4a0d |
line wrap: on
line source
#require unix-permissions no-root no-windows Prepare $ hg init a $ echo a > a/a $ hg -R a ci -A -m a adding a $ hg clone a b updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved Test that raising an exception in the release function doesn't cause the lock to choke $ cat > testlock.py << EOF > from mercurial import error, registrar > > cmdtable = {} > command = registrar.command(cmdtable) > > def acquiretestlock(repo, releaseexc): > def unlock(): > if releaseexc: > raise error.Abort(b'expected release exception') > l = repo._lock(repo.vfs, b'testlock', False, unlock, None, b'test lock') > return l > > @command(b'testlockexc') > def testlockexc(ui, repo): > testlock = acquiretestlock(repo, True) > try: > testlock.release() > finally: > try: > testlock = acquiretestlock(repo, False) > except error.LockHeld: > raise error.Abort(b'lockfile on disk even after releasing!') > testlock.release() > EOF $ cat >> $HGRCPATH << EOF > [extensions] > testlock=$TESTTMP/testlock.py > EOF $ hg -R b testlockexc abort: expected release exception [255] One process waiting for another $ cat > hooks.py << EOF > import time > def sleepone(**x): time.sleep(1) > def sleephalf(**x): time.sleep(0.5) > EOF $ echo b > b/b $ hg -R b ci -A -m b --config hooks.precommit="python:`pwd`/hooks.py:sleepone" > stdout & $ hg -R b up -q --config ui.timeout.warn=0 --config hooks.pre-update="python:`pwd`/hooks.py:sleephalf" \ > > preup-stdout 2>preup-stderr $ wait $ cat preup-stdout $ cat preup-stderr waiting for lock on working directory of b held by process '*' on host '*' (glob) got lock after * seconds (glob) $ cat stdout adding b On processs waiting on another, warning after a long time. $ echo b > b/c $ hg -R b ci -A -m b --config hooks.precommit="python:`pwd`/hooks.py:sleepone" > stdout & $ hg -R b up -q --config hooks.pre-update="python:`pwd`/hooks.py:sleephalf" \ > --config ui.timeout.warn=250 \ > > preup-stdout 2>preup-stderr $ wait $ cat preup-stdout $ cat preup-stderr $ cat stdout adding c On processs waiting on another, warning disabled. $ echo b > b/d $ hg -R b ci -A -m b --config hooks.precommit="python:`pwd`/hooks.py:sleepone" > stdout & $ hg -R b up -q --config hooks.pre-update="python:`pwd`/hooks.py:sleephalf" \ > --config ui.timeout.warn=-1 \ > > preup-stdout 2>preup-stderr $ wait $ cat preup-stdout $ cat preup-stderr $ cat stdout adding d check we still print debug output On processs waiting on another, warning after a long time (debug output on) $ echo b > b/e $ hg -R b ci -A -m b --config hooks.precommit="python:`pwd`/hooks.py:sleepone" > stdout & $ hg -R b up --config hooks.pre-update="python:`pwd`/hooks.py:sleephalf" \ > --config ui.timeout.warn=250 --debug\ > > preup-stdout 2>preup-stderr $ wait $ cat preup-stdout calling hook pre-update: hghook_pre-update.sleephalf waiting for lock on working directory of b held by process '*' on host '*' (glob) got lock after * seconds (glob) 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cat preup-stderr $ cat stdout adding e On processs waiting on another, warning disabled, (debug output on) $ echo b > b/f $ hg -R b ci -A -m b --config hooks.precommit="python:`pwd`/hooks.py:sleepone" > stdout & $ hg -R b up --config hooks.pre-update="python:`pwd`/hooks.py:sleephalf" \ > --config ui.timeout.warn=-1 --debug\ > > preup-stdout 2>preup-stderr $ wait $ cat preup-stdout calling hook pre-update: hghook_pre-update.sleephalf waiting for lock on working directory of b held by process '*' on host '*' (glob) got lock after * seconds (glob) 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cat preup-stderr $ cat stdout adding f Pushing to a local read-only repo that can't be locked $ chmod 100 a/.hg/store $ hg -R b push a pushing to a searching for changes abort: could not lock repository a: Permission denied [20] $ chmod 700 a/.hg/store