503 Error: Submitting large form with many input variables


I am developing script so my members can submit a table of information through an HTML form. This table can sometimes grow to include thousands of input boxes (very large HTML form submission).

These input types are either hidden or text, typically between 1-20 characters per field. When I submit the form with around 1,200 input fields boxes, it goes through fine.

The latest test had just under 4,000 input fields and I got this 503 error upon submission:
Service Temporarily Unavailable

The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.

This physical memory size of the post is nowhere near the maximum allowed in a $_POST variable (post_max_size = 32M). In addition, I changed my PHPRC file to increase the number of input vars to: max_input_vars = 50000

This still doesn’t seem to help and it appears to be an issue with something crashing on the server. Please let me know why this might be happening.

Kind regards

Additional Info:

I also have PHP version 5.4 and phpinfo() is showing that max_input_vars = 50000 . It seems that the PHPRC file is working, but the script is still failing with the 503 Error: Service Temporarily Unavailable. Basically, I’m trying to allow members to create multiple variations of products within an ecommerce setting, which can sometimes turn into very large combinations.

Please let me know what else might be crashing the script.