[5.x]: Mutex exception because of propagation method "Only save entries to the site they were created in" after upgrade from 4.x

[peter0503]

What happened?

Description

After upgrading from version 4.12.3 to 5.6.0.2, we encountered a mutex exception when creating a new page entry. This issue arises due to the propagation method "Only save entries to the site they were created in" on a field used in the entry type. If we switch to another propagation method, it works correctly. Previously, this field used a Super Table in version 4.x, and in version 5.x, we are using Matrix instead of the Super Table. We performed the migration through the console to migrate all Super Table fields.

Steps to reproduce

1. Upgrade from 4.12.3 to 5.6.0.2
2. Create a new "page entry"

Expected behavior

Should open me the entry and I should be able to fill out the the data

Actual behavior

Mutex Exception – craft\errors\MutexException
Unable to acquire a lock for the structure 1

Craft CMS version

Craft Pro 5.6.0.2

PHP version

8.3.16

Operating system and version

Linux 5.10.228-219.884.amzn2.x86_64

Database type and version

PostgreSQL 14.12

Image driver and version

GD 8.3.16

Installed plugins and versions

Plugin	Version
Amazon S3	2.2.1
Amazon SES	3.1.0
Code Field	5.0.0
Control Panel CSS	3.0.0
Control Panel JS	3.0.0
CP Field Inspect	2.0.3
Element Relations	3.0.6
Feed Me	6.6.1
Guide	5.2.0
Hyper	2.2.2
Icon Picker	3.0.2
ImageOptimize	5.0.4
Navigation	3.0.5
Neo	5.2.22
Preparse	3.0.0-alpha.2
Redactor	4.2.0
Retour	5.0.5
SEOmatic	5.1.10
Static Translations	4.1.1
Super Dynamic Fields	5.0.1
Super Table	4.0.2
Translations	v4.0.6
Workflow	3.0.5

[peter0503]

Update:
Only the "Save entries to all sites the owner element is saved in" does work. We can also provide a database dump if needed.

[i-just]

Hi, thanks for getting in touch. To start with, can you please post a full stack trace for the error you’re getting? Also, are you using a custom mutex component?

[peter0503]

We do not have a custom mutex entry in the app.php.

Stacktrace:

craft\errors\MutexException: Unable to acquire a lock for the structure 1 in /app/vendor/craftcms/cms/src/services/Structures.php:511
Stack trace:
#0 /app/vendor/craftcms/cms/src/services/Structures.php(375): craft\services\Structures->_doIt()
#1 /app/vendor/craftcms/cms/src/elements/Entry.php(2713): craft\services\Structures->appendToRoot()
#2 /app/vendor/craftcms/cms/src/elements/Entry.php(2654): craft\elements\Entry->_placeInStructure()
#3 /app/vendor/craftcms/cms/src/services/Elements.php(3775): craft\elements\Entry->afterSave()
#4 /app/vendor/craftcms/cms/src/services/Elements.php(1217): craft\services\Elements->craft\services\{closure}()
#5 /app/vendor/craftcms/cms/src/services/Elements.php(3580): craft\services\Elements->ensureBulkOp()
#6 /app/vendor/craftcms/cms/src/services/Elements.php(1303): craft\services\Elements->_saveElementInternal()
#7 /app/vendor/craftcms/cms/src/services/Drafts.php(261): craft\services\Elements->saveElement()
#8 /app/vendor/craftcms/cms/src/controllers/EntriesController.php(185): craft\services\Drafts->saveElementAsDraft()
#9 [internal function]: craft\controllers\EntriesController->actionCreate()
#10 /app/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array()
#11 /app/vendor/yiisoft/yii2/base/Controller.php(178): yii\base\InlineAction->runWithParams()
#12 /app/vendor/yiisoft/yii2/base/Module.php(552): yii\base\Controller->runAction()
#13 /app/vendor/craftcms/cms/src/web/Application.php(361): yii\base\Module->runAction()
#14 /app/vendor/yiisoft/yii2/web/Application.php(103): craft\web\Application->runAction()
#15 /app/vendor/craftcms/cms/src/web/Application.php(329): yii\web\Application->handleRequest()
#16 /app/vendor/yiisoft/yii2/base/Application.php(384): craft\web\Application->handleRequest()
#17 /app/web/index.php(21): yii\base\Application->run()
#18 {main}

[brandonkelly]

How exactly are you coming to the conclusion that the section’s propagation method is the culprit here? Have you tried changing the section’s propagation method? Or are you just not seeing the same issue with other sections (which have different propagation methods selected)?

I’m not able to reproduce the error regardless of propagation method.

The stack trace says the error is happening here:

cms/src/services/Structures.php

Lines 508 to 512 in 40fb91c

	$lockName = 'structure:' . $structureId;
	$mutex = Craft::$app->getMutex();
	if (!$mutex->acquire($lockName, $this->mutexTimeout)) {
	throw new MutexException($lockName, sprintf('Unable to acquire a lock for the structure %s', $structureId));
	}

Which is only going to get called once regardless of propagation method.

Most likely, the database has a lock on stucture:<ID> that didn’t get released properly for some reason. If you restart your database server, the error should go away.

[peter0503]

We nailed it down to a field. Then we removed the field and it does work. After adding it again it is failing again, so we tried to change the propagation method and as I mentioned above if we choose the ""Save entries to all sites the owner element is saved in" id does work, but for all other on this field it does not. Here is a screenshot of our field which causes this behavior.

As mentioned above, we could also provide a database dump.

We also restartet our system and also destroyed all containers, even the db container, since we are on aws.

[brandonkelly]

Can you send your database and Composer files into support@craftcms.com so we can look into it from our end?

[peter0503]

Sent you the required files to the mail mentioned.