Cron does not terminate and need a lot of ram

[devnull]

Yes. But if you use cron every 5 minutes it does not work because it runs multiple because of the long time of execution.

But perhaps it is a problem with your old operation system. With Ubuntu 20.04 LTS or Debian Buster 10 you get a newer php-version than php 7.0 . Which operation system is installed?

php 7.0 and Ubuntu:
https://packages.ubuntu.com/de/xenial/php
This is Ubuntu 16.04 LTS and very old.

php 7.0 and Debian:
https://packages.debian.org/de/stretch/php
This is Debian Stretch and also a little bit old.

Both systems are supported but perhaps not a good solution for nextcloud.
You must use for running nextcloud a php-version from another source than the normal distribution.

@Tealk144

Operating system and version: 18.04.4.LTS

https://packages.ubuntu.com/de/bionic/php
uses php 7.2

Perhaps you can dist-upgrade to Ubuntu 20.04 LTS

[tflidd]

In your database you have a table oc_jobs or jobs. This is a list of all jobs executed during a cronjob. There is even a column with execution duration.

With this list you can perhaps crosscheck with the apps installed if everything is working as supposed. From you apps, there is stuff like imageconverter which could create a lot of load on the system.

@Tealk144

if I start the cron by hand, it runs through without any problems.
No error message or similar can be detected.

That is great, and how long took the run?
The 5 minute cycle was changed recently, before it was about 15 minutes. Drawback of longer cycles are that notification mails will be sent with a larger delay. Normally the cronjob creates a lockfile, so there shouldn’t be any overlap (the new process makes sure the old one finished).
if everything takes long, you might take a look into your database caching settings.

If you have redis, I’d use it as file-locking cache as well that takes away load from the normal database.

[Tealk144]

since I have installed php 7.4, should this not be a problem for the time I think?

[Tealk144]

this execution duration is given in seconds? then it would be 86 seconds in total

so according to the github page of the imageconverter this is only done by hand

major-mayer/imageconverter

we have some iphone users, so I installed this.

I have now done it 3 times by hand and it takes maximum 2 minutes.

thanks for the tip with the redis filelock, have it set up now
https://docs.nextcloud.com/server/latest/admin_manual/configuration_server/caching_configuration.html?highlight=file%20lock%20redis#id2

since the changeover the cronjob also takes less than one minute

[tflidd]

Which task is taking most of the time?

With the reduction, did the memory consumption decrease as well?

[Tealk144]

i can’t say yet, because the cron seems to hang only 2 times a day

[tflidd]

then it’s just a matter of time. Don’t forget to dump the jobs-table so you can track this issue. I’m not sure about the logs (perhaps needs to increase log level), perhaps there it’s mentioned which job is started, so in case of a crash you just need to check which one was started last.

[Tealk144]

These are the 3 biggest jobs, then come 10 or so with an execution time of 1

OCA\Activity\BackgroundJob\ExpireActivities 	16
OCA\Files_Versions\BackgroundJob\ExpireVersions 	15
OCA\Files\BackgroundJob\ScanFiles 	15

[Tealk144]

@tflidd

then it’s just a matter of time. Don’t forget to dump the jobs-table so you can track this issue. I’m not sure about the logs (perhaps needs to increase log level), perhaps there it’s mentioned which job is started, so in case of a crash you just need to check which one was started last.

so I can just empty the oc_jobs?

[Chris_Aldred]

I am having this exact problem, I have ensured the php config has been done correctly. This has only started after I have moved to nextcloud 19, could this be an issue with php7.4 ?

Nextcloud version: 19.0.0
Operating system and version: 20.04 LTS
Apache or nginx version: nginx/1.18.0 (fpm-fcgi)
Database: mysql 10.1.44
PHP version: 7.4.8

[tflidd]

@Tealk144

so I can just empty the oc_jobs?

No just backup the table after each run to see how long it took. Don’t empty the table, it’s needed.

[Tealk144]

so i couldn’t see any difference except for the new timestamps, i started an excerpt here.

The problem is that the cron gets stuck at night and I would rather sleep than wait for the cron

but it always seems to get stuck at the same time; once at 23:30 and at 5:30(CEST)

but I have to agree @Chris_Aldred , I’ve only had this problem since Nextcloud 19
Whereby only on the Ubuntu system, I manage another one on Debian and there it does not occur, the configuration is almost identical

[tflidd]

@Tealk144

than wait for the cron

You can run a cron afterwards to query the values from the database. Also the logs might give hints

@Tealk144

once at 23:30 and at 5:30(CEST)

I am not sure if all the jobs do something at each run. Like this, I’d think that these are some daily routines, not sure like for the trashbin and stuff like that. But I don’t know enough to tell you which has changed for NC 19. Perhaps change the run time a bit, perhaps on your ubuntu system it collides with a different cronjob.

[Tealk144]

Ok I have now set up the whole system on a brand new Debian server and migrated the data. But I still have the problem somehow.
I really don’t know what it is

[h3rb3rt]

I runinng into issues with cron too and having a hard time to figure it out.
I added my comment to another thread and thought linking would be helpful

Cron.php takes too long and can end up running multiple times

I am facing the same, since upgraded to 19.x Any tips to figure out why a cron is running for over 1,5 hours and not getting finished? I figured out, using the oc_jobs table that the task OCA\Files\BackgroundJob\ScanFiles already lasted for 6747 seconds (if the value is in seconds).

[h3rb3rt]

Background Job ScanFiles triggered via cron.php breaks my system

Hi, I have realized that my cron is taken quite some time to finish. After some investigation I found that the job OCA\Files\BackgroundJob\ScanFiles is triggered via the oc_jobs table in my database. The job does not run every time cron is started (which would be every 5 minutes) but at least twice a day. Why ? I mean, why is it scanning all my files for new / changes files. My server hosts around 1,5 TB of data, this takes forever and I am not getting the idea of it. I would understand if I …

I am really struggling, so I link this thread here too.

[mdthh]

Same problem here. cron.php takes up to 90% of 4GB RAM und 30% of CPU for aprox. 30 secs.

Following tflidd’s advice:

select * from oc_jobs ORDER BY execution_duration DeSC;
+------+-----------------------------------------------------------------+--------------------------------------------------------------------------+------------+--------------+-------------+--------------------+
| id   | class                                                           | argument                                                                 | last_run   | last_checked | reserved_at | execution_duration |
+------+-----------------------------------------------------------------+--------------------------------------------------------------------------+------------+--------------+-------------+--------------------+
|   24 | OCA\UpdateNotification\Notification\BackgroundJob               | null                                                                     | 1617940802 |   1618023302 |           0 |                 27 |
|    1 | OCA\NextcloudAnnouncements\Cron\Crawler                         | null                                                                     | 1618001701 |   1618023302 |           0 |                  1 |
|   44 | OCA\Passwords\Cron\CheckPasswordsJob                            | null                                                                     | 1617940829 |   1618023302 |           0 |                  1 |
|   48 | OCA\Passwords\Cron\BackupJob                                    | null                                                                     | 1617940830 |   1618023302 |           0 |                  1 |
|   68 | OCA\Deck\Cron\ScheduledNotifications                            | null                                                                     | 1618023302 |   1618023302 |           0 |                  0 |
|   30 | OCA\Talk\BackgroundJob\ExpireSignalingMessage                   | null                                                                     | 1618023002 |   1618023302 |           0 |                  0 |
|   31 | OCA\Talk\BackgroundJob\RemoveEmptyRooms                         | null                                                                     | 1618023002 |   1618023302 |           0 |                  0 |

Except for OCA\UpdateNotification\Notification\BackgroundJob everything fine.

sudo -u www-data php /var/www/vhosts/XXX/public/occ background:queue:status -vvv:
takes long, then “Getötet” - probably “Killed” in English

Same happens with:
sudo -u www-data php /var/www/vhosts/XXX/public/occ background:queue:status -vvv

Amy ideas? Thanks so much indeed.

[szaimen]

Hm… Sounds like [NC 21] OCC Update error: allowed memory size exhausted · Issue #25742 · nextcloud/server · GitHub

[mdthh]

szaimen, you were right! Following this advice, by adding:

'debug' => 'false', // note: string not bool
'loglevel' => 2,

to config/config.php solved the problem.

Thanks!

[flow-axel]

I found a problem with the Maps app in my NC installation. Had over 3650 lines of Maps AddPhotoJob lines in my oc_jobs (the cron job table for NC) table.

I uninstalled the Maps app and deleted the jobs from my oc_jobs table with:

DELETE FROM oc_jobs WHERE class LIKE ‘%Maps%’ and argument LIKE ‘%photoId%’;

Now my cron runs through in seconds and uses less than 200 MB of memory.
That helped a lot, especially on a Raspberry Pi, which started swapping a few Gigabytes of RAM everytime the cronjob ran through.

You can also try this by hand then:

sudo -u www-data php -d memory_limit=512M -f /var/www/nextcloud/cron.php --define apc.enable_cli=1

With limited the php memory usage down to 512 MB. When the Maps AddPhotoJobs were still in, this command crashed with:

“PHP Fatal error: Allowed memory size of 536870912 bytes exhausted (tried to allocate 49752824 bytes) in /var/www/nextcloud/apps/maps/lib/Helper”

Which was also a good indication where the whole RAM usage came from