Old chunk files in cache folder

Nextcloud version: 12.0.1
Operating system and version: debian 8.9
Apache or nginx version: Apache 2.4
PHP version: 7.1.8

The issue you are facing:
Some gb of files ending on e.g. …-chunking-1692055206-7 with a size of 10MB are left behind in a users cache folder. They are all originating from one bigger file the user was working on. I guess the uploads did not complete due to standby, relogging, shutdown, etc. The files are between one to two weeks old.
This is set for chunk ttl: ‘cache_chunk_gc_ttl’ => 86400, . The cronjob is running correctly every 15 min.
Obviously the files did not get deleted after the defined ttl.

Will they be deleted or is there a way to savely manually delete them?

The output of your Nextcloud:
Nothing in log for the issue.

The output of your config.php file:

‘installed’ => true,`
‘memcache.local’ => ‘\OC\Memcache\APCu’,
‘filelocking.enabled’ => true,
‘memcache.locking’ => ‘\OC\Memcache\Redis’,
‘redis’ =>
array (
‘host’ => ‘localhost’,
‘port’ => XYZF,
‘timeout’ => 0,

‘loglevel’ => 2,
‘log_rotate_size’ => 10485760,
‘trashbin_retention_obligation’ => ‘auto, 7’,
‘versions_retention_obligation’ => ‘auto, 7’,
‘cache_chunk_gc_ttl’ => 86400,

We had such questions in the past. In general, it was save to delete these files. I would keep a copy just in case you remove something important, perhaps do a full backup before as well. I would only investigate further if such files reappear and are not deleted. Although it would be interesting to know why this happened.

Thank you.
Deleted them after snapshot and backup. An ./occ files:scan --all and ./occ files:cleanup took care of the database entries. No problems so far.
The affected User account syncs via mac client and worked on a quite large keynote file > 150 MB with a lot of saving and autosaving going on which lead to a multiple versions and new syncs before the last version has been completely uploaded. Maybe something went wrong there…
Will look more closely and consult the audit log next time.