##// END OF EJS Templates
bookmarks: actual fix for race condition deleting bookmark...
bookmarks: actual fix for race condition deleting bookmark This is a simple but efficient fix to prevent the issue tested in `test-bookmarks-corner-case.t`. It might be worth pursuing a more generic approach where filecache learn to depend on each other, but that would not be suitable for stable. The issue is complicated enough that I documented the race and its current solution as inline comment. See this comment for details on the fix.

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test-bookmarks-corner-case.t
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/ tests / test-bookmarks-corner-case.t
bookmark: add a test for a race condition on push...
r42538 ================================
Test corner case around bookmark
================================
This test file is meant to gather test around bookmark that are specific
enough to not find a place elsewhere.
Test bookmark/changelog race condition
======================================
The data from the bookmark file are filtered to only contains bookmark with
node known to the changelog. If the cache invalidation between these two bits
goes wrong, bookmark can be dropped.
global setup
------------
$ cat >> $HGRCPATH << EOF
> [ui]
> ssh = "$PYTHON" "$TESTDIR/dummyssh"
> [server]
> concurrent-push-mode=check-related
> EOF
Setup
-----
initial repository setup
$ hg init bookrace-server
$ cd bookrace-server
$ echo a > a
$ hg add a
$ hg commit -m root
$ echo a >> a
$ hg bookmark book-A
$ hg commit -m A0
$ hg up 'desc(root)'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(leaving bookmark book-A)
$ echo b > b
$ hg add b
$ hg bookmark book-B
$ hg commit -m B0
created new head
$ hg up null
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
(leaving bookmark book-B)
$ hg phase --public --rev 'all()'
$ hg log -G
o changeset: 2:c79985706978
| bookmark: book-B
| tag: tip
| parent: 0:6569b5a81c7e
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B0
|
| o changeset: 1:39c28d785860
|/ bookmark: book-A
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: A0
|
o changeset: 0:6569b5a81c7e
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: root
$ hg book
book-A 1:39c28d785860
book-B 2:c79985706978
$ cd ..
Add new changeset on each bookmark in distinct clones
$ hg clone ssh://user@dummy/bookrace-server client-A
requesting all changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 2 files (+1 heads)
new changesets 6569b5a81c7e:c79985706978
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg -R client-A update book-A
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(activating bookmark book-A)
$ echo a >> client-A/a
$ hg -R client-A commit -m A1
$ hg clone ssh://user@dummy/bookrace-server client-B
requesting all changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 2 files (+1 heads)
new changesets 6569b5a81c7e:c79985706978
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg -R client-B update book-B
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(activating bookmark book-B)
$ echo b >> client-B/b
$ hg -R client-B commit -m B1
extension to reproduce the race
-------------------------------
If two process are pushing we want to make sure the following happens:
* process A read changelog
* process B to its full push
* process A read bookmarks
* process A proceed with rest of the push
We build a server side extension for this purpose
$ cat > bookrace.py << EOF
> import os
> import time
> import atexit
> from mercurial import error, extensions, bookmarks
test: factor out the "wait" logic in bookrace...
r42707 >
test: add some assert in the bookrace extension...
r42708 > def wait(repo):
bookmark: add a test for a race condition on push...
r42538 > if not os.path.exists('push-A-started'):
test: add some assert in the bookrace extension...
r42708 > assert repo._currentlock(repo._lockref) is None
> assert repo._currentlock(repo._wlockref) is None
bookmark: add a test for a race condition on push...
r42538 > print('setting raced push up')
> with open('push-A-started', 'w'):
> pass
> clock = 300
> while not os.path.exists('push-B-done'):
> clock -= 1
> if clock <= 0:
> raise error.Abort("race scenario timed out")
> time.sleep(0.1)
test: factor out the "wait" logic in bookrace...
r42707 >
bookmarks: actually trigger the race deleting bookmark in the test...
r42709 > def reposetup(ui, repo):
> class racedrepo(repo.__class__):
> @property
> def _bookmarks(self):
> wait(self)
> return super(racedrepo, self)._bookmarks
> repo.__class__ = racedrepo
>
bookmark: add a test for a race condition on push...
r42538 > def e():
> with open('push-A-done', 'w'):
> pass
> atexit.register(e)
> EOF
Actual test
-----------
Start the raced push.
$ cat >> bookrace-server/.hg/hgrc << EOF
> [extensions]
> bookrace=$TESTTMP/bookrace.py
> EOF
$ hg push -R client-A -r book-A >push-output.txt 2>&1 &
Wait up to 30 seconds for that push to start.
$ clock=30
$ while [ ! -f push-A-started ] && [ $clock -gt 0 ] ; do
> clock=`expr $clock - 1`
> sleep 1
> done
Do the other push.
$ cat >> bookrace-server/.hg/hgrc << EOF
> [extensions]
> bookrace=!
> EOF
$ hg push -R client-B -r book-B
pushing to ssh://user@dummy/bookrace-server
searching for changes
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
updating bookmark book-B
Signal the raced put that we are done (it waits up to 30 seconds).
$ touch push-B-done
Wait for the raced push to finish (with the remaning of the initial 30 seconds).
$ while [ ! -f push-A-done ] && [ $clock -gt 0 ] ; do
> clock=`expr $clock - 1`
> sleep 1
> done
Check raced push output.
$ cat push-output.txt
pushing to ssh://user@dummy/bookrace-server
searching for changes
bookmarks: actual fix for race condition deleting bookmark...
r42711 remote has heads on branch 'default' that are not known locally: f26c3b5167d1
bookmark: add a test for a race condition on push...
r42538 remote: setting raced push up
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
updating bookmark book-A
Check result of the push.
$ hg -R bookrace-server log -G
o changeset: 4:9ce3b28c16de
| bookmark: book-A
| tag: tip
| parent: 1:39c28d785860
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: A1
|
| o changeset: 3:f26c3b5167d1
bookmarks: actual fix for race condition deleting bookmark...
r42711 | | bookmark: book-B
bookmark: add a test for a race condition on push...
r42538 | | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: B1
| |
| o changeset: 2:c79985706978
| | parent: 0:6569b5a81c7e
| | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: B0
| |
o | changeset: 1:39c28d785860
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: A0
|
o changeset: 0:6569b5a81c7e
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: root
$ hg -R bookrace-server book
book-A 4:9ce3b28c16de
bookmarks: actual fix for race condition deleting bookmark...
r42711 book-B 3:f26c3b5167d1