PHP downloads: Problems with Large files

I’ve been having some problems with a PHP download script (posted here http://modxcms.com/forums/index.php/topic,38940.msg235780.html#msg235780)

But I seem to have worked most things out... except if the file is really large. Then I get Internal Server Errors (when the file is bigger than 50mb). I’ve tried changing the php.ini, I’ve tried working with various chunk download scripts (e.g. the "chunk" script here: http://us.php.net/manual/en/function.readfile.php ), but nothing seems to solve the problem: smaller files stream fine, but larger files produce the error.

Does anyone have a solid PHP download script that handles large files? Why is this such a pain? Is it PHP’s loose memory allocation? Phase of the moon?

Usually, it’s just shenanigans. In all seriousness, my understanding is that large file transfers over http:// using PHP can be problematic. I hate to suggest it in this case, but I really do think some Googling around would probably be a good start.

The Apache server can also be configured to limit download sizes. Perhaps looking into PHP’s FTP functions would be helpful.

Yeah, ok... we were hoping not to come to FTP, but the googling I’ve done also suggests that this is simply problematic. Perl anyone?

If it’s an Internal Server Error, it is most likely an Apache (or PHP) configuration problem (checking the Apache error_log may help here), not a problem with PHP’s readfile function, but I don’t think you need to use the chunk version from the documentation.

Yeah, I’d like to look at the log file, but it’s on a grid server, and it’s not easy to check (maybe not possible?). This would be much easier to debug on a stand-alone server.

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