Laravel queue:listen takes up all the server memory all the time

I am using Amazon Beanstalk to host my Laravel Application. I created a special configuration so that my queue:listen will auto re-start on deployment with supervisor.

[unix_http_server]
file=/tmp/supervisor.sock
chmod=0777

[supervisord]
logfile=/var/app/support/logs/supervisord.log
logfile_maxbytes=25MB
logfile_backups=2
loglevel=warn
pidfile=/var/run/supervisord/supervisord.pid
nodaemon=false
nocleanup=true
user=webapp

[program:laravel_queue]
command=php artisan queue:listen --queue=email,activity,purging,misca --memory=256 --env=production
directory=/var/app/current
stdout_logfile=/var/app/support/logs/laravel-queue.log
logfile_maxbytes=25MB
logfile_backups=2
redirect_stderr=true
autostart=true
autorestart=true
startretries=86400

This works great and my problem is after a day or too my server memory always reaches 95%!

I inspected the memory and noticed a bunch of http processes that were started by queue:listen but for some reason never killed (note all jobs succeeded, no failure).

webapp   22923  0.0  0.4 673948 19032 ?        S    18:10   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22926  0.0  0.8 674588 35512 ?        S    18:10   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22929  0.0  0.4 673948 19032 ?        S    18:11   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22931  0.0  0.9 674932 37576 ?        S    18:11   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22932  0.0  0.4 673948 19032 ?        S    18:11   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22934  0.0  0.8 674600 35536 ?        S    18:11   0:00 /usr/sbin/httpd -D FOREGROUND
webapp   22935  0.0  0.8 674588 35512 ?        S    18:11   0:00 /usr/sbin/httpd -D FOREGROUND

Why are these http processes which I assume are queue:workers not terminating?

via Chebli Mohamed