Cron.php runs forever

[icyground]

Steps to reproduce

1. run cron.php via system cron

Expected behaviour

cron should do the tasks from oc_jobs table and finish them in a resonable time.

Actual behaviour

In my instance once a day a job spawns, which runs forever (at least as I can interpolate ;) )
It takes 100% CPU distributed between cron.php and mysql, and creates no log entries or error messages.
The Queries against the mysql server are always DELETE FROM `oc_properties` WHERE `fileid` IN (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
The amount of rows in oc_properties stays the same meanwhile (~32000).
The only thing to end this is to kill the php processes, but they reappear every day if the cronjob is activated.
The instance is running fine regarding all other aspects.

Content of oc_jobs:

+-------+---------------------------------------------------+-------------------------------------------------------+------------+--------------+-------------+--------------------+
| id    | class                                             | argument                                              | last_run   | last_checked | reserved_at | execution_duration |
+-------+---------------------------------------------------+-------------------------------------------------------+------------+--------------+-------------+--------------------+
|     1 | OC\BackgroundJob\Legacy\RegularJob                | ["\\OC\\Files\\Cache\\BackgroundWatcher","checkNext"] | 1555346702 |   1555346702 |           0 |                  0 |
| 14382 | OCA\Activity\BackgroundJob\EmailNotification      | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 14383 | OC\BackgroundJob\Legacy\RegularJob                | ["OCA\\Music\\Backgroundjob\\CleanUp","run"]          | 1555346702 |   1555346702 |           0 |                  0 |
| 14393 | OCA\Activity\BackgroundJob\ExpireActivities       | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
| 18389 | OCA\Files_Trashbin\BackgroundJob\ExpireTrash      | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 18390 | OCA\Files_Versions\BackgroundJob\ExpireVersions   | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 18481 | OCA\Files\BackgroundJob\ScanFiles                 | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 18482 | OCA\Files\BackgroundJob\DeleteOrphanedItems       | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 18483 | OCA\Files\BackgroundJob\CleanupFileLocks          | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 18485 | OCA\Federation\SyncJob                            | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
| 18486 | OCA\DAV\CardDAV\SyncJob                           | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
| 19250 | \OC\Authentication\Token\DefaultTokenCleanupJob   | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 19251 | OCA\UpdateNotification\Notification\BackgroundJob | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
| 19253 | OCA\DAV\CardDAV\Sync\SyncJob                      | null                                                  |          0 |   1555335001 |  1555335001 |                 -1 |
| 19254 | OCA\Files_Sharing\DeleteOrphanedSharesJob         | null                                                  | 1555346702 |   1555346702 |           0 |                  0 |
| 19255 | OCA\Files_Sharing\ExpireSharesJob                 | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
| 19256 | OC\Log\Rotate                                     | "\/srv\/owncloud\/data\/owncloud.log"                 | 1555346702 |   1555346702 |           0 |                  0 |
| 20494 | OCA\Market\CheckUpdateBackgroundJob               | null                                                  | 1555338601 |   1555346702 |           0 |                  1 |
| 20499 | OC\Log\Rotate                                     | "owncloud2.log"                                       | 1555346702 |   1555346702 |           0 |                  0 |
| 20500 | OC\Log\Rotate                                     | "\/srv\/owncloud\/data\/owncloud2.log"                | 1555346702 |   1555346702 |           0 |                  0 |
| 20681 | OCA\DAV\BackgroundJob\CleanProperties             | null                                                  | 1555341302 |   1555341302 |  1555341302 |                 -1 |
| 20682 | OCA\BruteForceProtection\Jobs\ExpireOldAttempts   | null                                                  | 1555338602 |   1555346702 |           0 |                  0 |
+-------+---------------------------------------------------+-------------------------------------------------------+------------+--------------+-------------+--------------------+

Server configuration

Operating system:
Ubuntu 18.04

Web server:
Apache/2.4.29 (Ubuntu)

Database:
mysql Ver 15.1 Distrib 10.1.38-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

PHP version:
PHP 7.2.15-0ubuntu0.18.04.2

ownCloud version: (see ownCloud admin page)
10.1.1.1

Updated from an older ownCloud or fresh install:
updated

Where did you install ownCloud from:
Official repository

Signing status (ownCloud 9.0 and above):
No errors have been found.

The content of config/config.php:

{                           
    "system": {       
        "instanceid": "***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "datadirectory": "\/srv\/owncloud\/data",
        "dbtype": "mysql",          
        "version": "10.1.1.1",

        "dbname": "owncloud",
        "dbhost": "localhost",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "theme": "",
        "maintenance": false,
        "trusted_domains": [
          "***",
          "***",
          "***",
          "***"
          ],
          "mail_smtpmode": "smtp",
          "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
          "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
          "forcessl": true,
          "mail_from_address": "***REMOVED SENSITIVE VALUE***",
          "mail_domain": "***REMOVED SENSITIVE VALUE***",
          "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
          "mail_smtpport": "25",
          "secret": "***REMOVED SENSITIVE VALUE***",
          "logtimezone": "Europe\/Berlin",
          "log_type": "owncloud",
          "logfile": "\/srv\/owncloud\/data\/owncloud2.log",
          "log_rotate_size": 10485760,
          "log_authfailip": true,
          "loglevel": 2,
          "filelocking.enabled": true,
          "trashbin_retention_obligation": "auto",
          "appstore.experimental.enabled": true,
          "htaccess.RewriteBase": "\/",
          "memcache.local": "\\OC\\Memcache\\Redis",
          "memcache.locking": "\\OC\\Memcache\\Redis",
          "redis": {
            "host": "localhost",
            "port": 6379,
            "timeout": 0
            },
            "updatechecker": false,
            "updater.server.url": "https:\/\/updates.owncloud.com\/server\/",
            "has_internet_connection": true,
            "trusted_proxies": [
              "10.1.1.1"
            ],
            "overwritehost": "***",
            "overwritewebroot": "\/",
            "overwriteprotocol": "https"
}
}

List of activated apps:

Enabled:
  - activity: 2.4.2
  - bookmarks: 0.10.5
  - brute_force_protection: 1.0.1
  - calendar: 1.6.2
  - comments: 0.3.0
  - configreport: 0.1.2
  - contacts: 1.5.5
  - dav: 0.4.0
  - federatedfilesharing: 0.3.1
  - federation: 0.1.0
  - files: 1.5.2
  - files_external: 0.7.1
  - files_pdfviewer: 0.11.0
  - files_sharing: 0.11.0
  - files_texteditor: 2.3.0
  - files_trashbin: 0.9.1
  - files_versions: 1.3.0
  - files_videoplayer: 0.9.9
  - firstrunwizard: 1.1.1
  - gallery: 16.1.1
  - market: 0.4.0
  - notes: 2.0.4
  - notifications: 0.4.1
  - provisioning_api: 0.5.0
  - systemtags: 0.3.0
  - tasks: 0.9.7
  - twofactor_totp: 0.5.3
  - updatenotification: 0.2.1
Disabled:
  - encryption
  - external
  - user_external

Are you using external storage, if yes which one: no

Are you using encryption: no

Are you using an external user-backend, if yes which one: no

Client configuration

not applicable

Logs

Web server error log

no applicable Webserver Logs

ownCloud log (data/owncloud.log)

No relevant log in owncloud.log

Browser log

not applicable

I already seeked for help at the owncloud forum, unfortunately there was no suitable solution within a couple weeks.

[icyground]

Thanks! Your commit solves my problem.
Cheers to you!

[skazi0]

@icyground check my PR again. There is a new version of this fix as the old one broke the original functionality while fixing the bug.

[sharidas]

Reopening the ticket and here is the PR:
#36062

[sharidas]

This is in a blocked state as we need input from @skazi0 regarding how to reproduce the issue. I have also commented here: #35407 (comment)

[PVince81]

@sharidas I think it's fine to merge the cleanup job as it will already solve issues.

if we do find out the root cause then we can address it as well

[sharidas]

A better approach here is in this PR #36084. The fix is made in the db, hence it has migration change.

We can ignore the PR for now. Once the above PR is merged, I will close old pr too.