Imager X fails with low ImageMagick limits

[dgsiegel]

I'm submitting a...

• bug report
• feature request
• general question

Steps to reproduce

1. Set up a transformation for a volume with plenty of transformations
2. Use ImageMagick as Image drive
3. Transform images in a volume and see some images fail

Description

Unfortunately our hosting provider set quite low ImageMagick limits (/etc/ImageMagick-6/policy.xml):

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE policymap [
  <!ELEMENT policymap (policy)*>
  <!ATTLIST policymap xmlns CDATA #FIXED ''>
  <!ELEMENT policy EMPTY>
  <!ATTLIST policy xmlns CDATA #FIXED '' domain NMTOKEN #REQUIRED
    name NMTOKEN #IMPLIED pattern CDATA #IMPLIED rights NMTOKEN #IMPLIED
    stealth NMTOKEN #IMPLIED value CDATA #IMPLIED>
]>
<policymap>
  <policy domain="resource" name="memory" value="256MiB"/>
  <policy domain="resource" name="map" value="512MiB"/>
  <policy domain="resource" name="width" value="16KP"/>
  <policy domain="resource" name="height" value="16KP"/>
  <policy domain="resource" name="area" value="128MP"/>
  <policy domain="resource" name="disk" value="1GiB"/>
</policymap>

Our transforms are set up like this

<?php

return [
  'p' => [
    'transforms' => [
      ['width' => 576],
      ['width' => 768],
      ['width' => 992],
      ['width' => 1200],
      ['width' => 1400],
      ['width' => 1680],
      ['width' => 1920],
    ],
  ],
];

Our pregenerate config like this

<?php

return [
  'volumes' => [
    'press'   => ['p'],
  ],
];

When running /craft imager-x/generate -v press --interactive 0 we get the following error message in console.log:

2022-09-12 12:55:24 [-][-][-][error][spacecatninja\imagerx\transformers\CraftTransformer::getTransformedImage] An error occured when trying to open image: Unable to open image /nfs/web_mwn/www/2/***/webserver/htdocs/assets/press/Bild7.jpg

Looking further into the exception, I can find this message:

[...]
    [previous:Exception:private] => ImagickException Object
        (
            [message:protected] => cache resources exhausted `/nfs/web_mwn/www/2/klk1102/webserver/htdocs/assets/press/Bild7.jpg' @ error/cache.c/OpenPixelCache/4095
            [string:Exception:private] =>
            [code:protected] => 445
            [file:protected] => /nfs/web_mwn/www/2/klk1102/webserver/vendor/pixelandtonic/imagine/src/Imagick/Imagine.php
            [line:protected] => 69
[...]

So it seems that this transformation hits the ceiling of the 256MiB memory limit and fails.

Using fewer transformations, like the following seems to work (but is obviously not our goal):

<?php

return [
  'p' => [
    'transforms' => [
      ['width' => 576],
      ['width' => 768],
    ],
  ],
];

Also, setting instanceReuseEnabled to true reduces the amount of failing images, but does not work for all. Switching to GD as image driver also seems to do the trick.

Here's one example of a failing image:

Additional info

• Imager version & edition: v3.6.3.1 Pro
• Imager transformer: craft
• Craft version: 3.7.53.1
• PHP version: 8.0.20
• Image driver & version: Imagick 3.6.0 (ImageMagick 6.9.11-60)