[Gallery] slow loading the Picture Previews

Hello,

i would view some Pictures, saved on my Nextcloud, but the Preview Picture generation is very slowly.


Nextcloud version (eg, 10.0.2):
Operating system and version (eg, Ubuntu 16.04):
Apache or nginx version (eg, Apache 2.4.25):
PHP version (eg, 5.6):
Is this the first time you’ve seen this error?:

Can you reliably replicate it? (If so, please outline steps):

The issue you are facing:

The output of your Nextcloud log in Admin > Logging:

Error Exception: Preview generation has failed

Error	PHP	imagecreatefromstring(): Data is not in a recognized format at /var/www/nextcloud/lib/private/legacy/image.php#628

What can i do?

My System:


Odroid C2
2 GB RAM
Quadcore CPU.
Nextcloud 12.0.3
Ubuntu 16.04.03 LTS

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}

Can anyone help me?

Not only very slow, NC is unusable at this point!!!

Environment:

  • Gallery 17.0.0
  • Redis installed
  • NC 12.0.3

Issue:

  • Generating thumbnails stopps at every 6 pictures for a while of about 30 sec
  • Opening a picture takes from 10 to 20 sec

Generating thunbnails or trying to display pictures results always in similar like this CPU load:

Redis is configured in config.php like that:

'memcache.local' => '\OC\Memcache\APCu',
'memcache.locking' => '\OC\Memcache\Redis',
'redis' => array(
   'host' => '127.0.0.1',
   'port' => 6379,
 ),