[5.8] Allocate memory for error handling to allow handling memory exhaustion limits

[skylerfenn]

Allots 10kb of memory for "memory exhaustion" errors.

It lets the application give a more descriptive error than the default Fatal Error that is thrown for memory exhaustion.

The concept was taken from Symfony's error handler: https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/ErrorHandler/ErrorHandler.php.

[taylorotwell]

Provide before and after screenshots of the difference in error messages please.

[GrahamCampbell]

This solution won't work, however, in the case that this method is called more than once?

[GrahamCampbell]

Is setting to null actually guaranteed to release the memory. How does PHP calculate this? Do we have to wait for the garbage collector?

[laurencei]

Also - whats the performance hit (if any) on running the 'x' repeat command 10240 times? Both in terms of time and memory?

[skylerfenn]

@taylorotwell
Current Error

Better Error

@GrahamCampbell
The bootstrap method will only run each bootstrapper once on a request:
https://github.com/laravel/framework/blob/5.8/src/Illuminate/Foundation/Http/Kernel.php#L161

From what I've been able to see, setting a variable to null frees the memory immediately.

@laurencei
The function is only running once with 1 byte. The PHP source for str_repeat shows: "Heavy optimization for situations where input string is 1 byte long". Do you know of a more efficient way to allocate 10kb? Again, this idea was taken from Symfony's error handler. Throughout the history of that project, I couldn't find any discussion on this.

Thanks for the feedback and comments!

[mfn]

I like this approach, very useful.

Though I would find it really nice if there was a bit of documentation on the proper on what it is for.

@skylerfenn do you think you could add that?

[cxlblm]

Memory is very expensive. Is that really reasonable?