Symfony 4 Production Mode ErrorHandling Pages Memory Exhausted

Question

I set my project to prod mode in .env and everything aside from the custom error pages seem to work.

I have this as my 404 twig template:

{# templates/bundles/TwigBundle/Exception/error404.html.twig #}
{% include 'builder/layout/header.html.twig' with {'title': '404'} %}

<img src="{{ assets('img/not-found.jpeg') }}" class="img-responsive"
     id="error-not-found-img" />

<div class="http-error-msg-container">
    <h1>404! Page Not Found</h1>
    <p>Don't despair, go back to <a href="{{ path('dashboard') }}">Home</a> and try again.</p>
</div>

{% include 'builder/layout/footer.html.twig' %}

and going to a non-existant page (say /dashboard/giorgoirdjfisejf) returns a blank page. So I added this to my index.php file:

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(-1);

to show the errors and I got this:

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes) in /var/www/solomon/vendor/monolog/monolog/src/Monolog/Handler/StreamHandler.php on line 107

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 32768 bytes) in /var/www/solomon/vendor/symfony/debug/Exception/OutOfMemoryException.php on line 1

I'm not quite sure why this causes an error and unable to debug. var/log/prod.log doesn't show anything, how do I resolve or better yet, how do I debug?

update

my prod/monolog.yaml file

monolog:
    handlers:
        main:
            type: fingers_crossed
            action_level: error
            handler: nested
            excluded_404s:
                # regex: exclude all 404 errors from the logs
                - ^/
        nested:
            type: stream
            path: "%kernel.logs_dir%/%kernel.environment%.log"
            level: debug
        console:
            type:   console
            process_psr_3_messages: false
            channels: ["!event", "!doctrine"]

this was auto-generated and I've made no changes

Answer 1

Check file permissions on symfony log files. It looks like monolog catches permission denied exception, tries to write it to log and catches same error again and again.