Lumen - Find memory leak

Hi,

My lumen application is running out of memory, even with a 512M memory limit. I'm trying to find where the leak is, but whenever an exception occur, I only receive the following trace:

Symfony\Component\Debug\Exception\FatalErrorException: Allowed memory size of 268435456 bytes exhausted (tried to allocate 62918656 bytes) 
in [PROJECT_DIRECTORY]\vendor\illuminate\http\Response.php:70
Stack trace:
    #0 [PROJECT_DIRECTORY]\vendor\laravel\lumen-        framework\src\Concerns\RegistersExceptionHandlers.php(54): Laravel\Lumen\Application->handleShutdown()
    #1 [internal function]: Laravel\Lumen\Application->Laravel\Lumen\Concerns\{closure}()
    #2 {main}

It doesn't show me where the leak actually happend, it shows me the trace of lumen's standard exception handlers. Is there efficient any way to find the leak ?

Sorry for any inconvinience with my english.