I have googled and binged and yahooed this question but can't seem to find an answer. I was working on a form that included over 800 fields but the form's submit function would never execute. After I pared the form down, the submit function ran. So now I'm curious if there's an actual built in maximum number of elements.
I think, the issue is related to Server configuration, not with Drupal.
max_input_vars variable in
php.ini which define the maximum number of variable form elements that can be submitted to a single page.
The “max_input_vars” setting in the php.ini file is a relatively new option starting last year from PHP 5.3.9. It allows you to control the maximum number of form elements on a page. Some webpages have a large amount of forms/fields for administrative or page configuration purposes. In those cases, we need to increase the number of this value in order to properly view those pages.
There is also
post_max_size variable in
post_max_sizesets max size of post data allowed. This setting also affects file upload. To upload large files, this value must be larger than
upload_max_filesize. If memory limit is enabled by your configure script,
memory_limitalso affects file uploading. Generally speaking, memory_limit should be larger than
post_max_size. If the size of post data is greater than
$_FILESsuperglobals are empty.
You can check the this for more details.