twice running cron.php / GenerateMetadataJob

[cypress-hill-car]

Due to problems with the endlessly running cron.php, I identified the issue by finding the "long running job." By obtaining the start time of the PID from ps and searching the logs, I discovered that the issue lies with the "GenerateMetadataJob," which is hanging. This job starts but never receives a "Finished" event:

{"reqId":"T7WSKkyswz0F035LClQ6","level":0,"time":"2024-01-27T10:00:03+00:00","remoteAddr":"","user":"--","app":"cron","method":"","url":"--","message":"Run OC\Core\BackgroundJobs\GenerateMetadataJob job with ID 36764","userAgent":"--","version":"28.0.1.1","data":{"app":"cron"}}

Additionally, the job is running twice or more:

[picard@borgcube ~]$ ps aux | grep -E "^http.*?cron.php$"
http     1944203 97.1  0.0 428316  4072 ?        R    Jan27 2821:33 php -f /srv/http/nextcloud/cron.php
http     1999635 96.8  0.2 428316 23768 ?        R    Jan28 1414:10 php -f /srv/http/nextcloud/cron.php
http     2055241 98.2  0.9 428316 75584 ?        R    11:05  19:55 php -f /srv/http/nextcloud/cron.php

[picard@borgcube ~]$ ps -p 1944203 -o lstart
                 STARTED
 Sat Jan 27 11:00:01 2024
[picard@borgcube ~]$ ps -p 1999635 -o lstart
                 STARTED
 Sun Jan 28 11:05:01 2024
[picard@borgcube ~]$ ps -p 2055241 -o lstart
                 STARTED
 Mon Jan 29 11:05:01 2024

I'm not sure why this is happening, but I have an idea that it might be related to symlinks and/or multiple mounted devices.

Additionally, while investigating this issue, I read some code and would like to recommend changing the "funny if/else construct" for checking "onlyTimeSensitive" at line 122ff in cron.php with this single line:

$onlyTimeSensitive = ($currentHour >= $startHour) == ($currentHour > $endHour);

Thanks a lot!

[cypress-hill-car]

Update

I tried the following:

• Disabled the cronjob when GenerateMetaData-Job has started and wait for three days if job ends...
  • Result: Job seems not end
• Run sudo -u http php /srv/www/nextcloud/occ files:scan --generate-metadata --all -v to check if generate-metadata will stuck also.
  • Result: Command works fine.

[pjft]

I agree with this report in that the GenerateMetaData takes too long, but I'm not convinced that that OCC command runs the exact same job.

When the cron job is running, if you start mysql and query the oc_files_metadata table, at least in my case I keep seeing new items being added. Alas, when I run the OCC task, it doesn't seem to create them - or maybe it just does all files, so it starts from the beginning and I just don't let it run to the end.

This is the query I'm running:

select * from oc_files_metadata inner join oc_filecache on file_id = fileid order by id desc limit 10;

and, in fact, just running

select * from oc_files_metadata order by id desc limit 10;

should show you new records.

In my case, I have over 1M entries in filecache, but 700k in metadata, so I imagine that it needs to run to the end. Alas, a regular maintenance reboot on my server stopped the cron job halfway through so I imagine it'll now need to be triggered again at some point.

[Morpheus1822]

To add a data point. After the upgrade from 29.0.2 to 29.0.9 the initial cron job took about three hours on my instance and generated the following warning in the log:

[cron] Warnung: Background job OC\Core\BackgroundJobs\GenerateMetadataJob (id: 26403, arguments: null) ran for 10921 seconds
    von ? von -- um 12.11.2024, 19:44:30

Any subsequently triggered cron job only took a few seconds or less and also triggering the GenerateMetadataJob finishied within seconds.

 sudo -u www-data ./occ background-job:list
<snip>
| 26403 | OC\Core\BackgroundJobs\GenerateMetadataJob                        | 2024-11-12T16:57:42+00:00 | null                                                                             
<snip>
 sudo -u www-data ./occ --force-execute background-job:execute 26403