PHP script stops processing input file after 5 seconds

I've written a PHP script that takes in two CSV files, processes them 开发者_StackOverflow社区and returns an HTML table. I developed it on my MacBook running on Apache. When I uploaded the script to our production server, it began having problems. Production is an Ubuntu 10.04 LTS running nginx that forwards requests to Apache/PHP.

I added some debugging statements and tailed the logs so I can see exactly where it's stopping the execution of the script, but there are no errors thrown anywhere. The first file is 1.9 MB and it processes 366 kb before it fails. I've tested this several times and it always fails at the same place. I don't believe it's the file as it's the same file I used for testing the script and it never had a problem on my MacBook.

I've searched the internet and have increased several timeout parameters in nginx to no avail. I'm not sure where to look or what to look for at this point. Can someone point me in the right direction?

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have you fully turned on error reporting on the server?