In Symfony 2.1, we have changed the listener priorities quite a bit. This should be documented somewhere and we should not do that again in future releases.

Here is the information we need to use for the documentation:

kernel.request

• Symfony\Component\HttpKernel\EventListener\ProfilerListener 1024
• Symfony\Bundle\FrameworkBundle\EventListener\TestSessionListener 192
• Symfony\Bundle\FrameworkBundle\EventListener\SessionListener 128
• Symfony\Component\HttpKernel\EventListener\RouterListener 32
• Symfony\Component\HttpKernel\EventListener\LocaleListener 16
• Symfony\Component\Security\Http\Firewall 8

kernel.controller

• Symfony\Bundle\FrameworkBundle\DataCollector\RequestDataCollector 0

kernel.response

• Symfony\Component\HttpKernel\EventListener\EsiListener 0
• Symfony\Component\HttpKernel\EventListener\ResponseListener 0
• Symfony\Bundle\SecurityBundle\EventListener\ResponseListener 0
• Symfony\Component\HttpKernel\EventListener\ProfilerListener -100
• Symfony\Bundle\FrameworkBundle\EventListener\TestSessionListener -128
• Symfony\Bundle\WebProfilerBundle\EventListener\WebDebugToolbarListener -128
• Symfony\Component\HttpKernel\EventListener\StreamedResponseListener -1024

kernel.exception

• Symfony\Component\HttpKernel\EventListener\ProfilerListener 0
• Symfony\Component\HttpKernel\EventListener\ExceptionListener -128

kernel.terminate

• Symfony\Bundle\SwiftmailerBundle\EventListener\EmailSenderListener 0

see symfony/symfony#2680 for the original report.