Post array incomplete when receiving a post - php

Question

I'm on a Drupal7 site, and I'm not used to Drupal. When I edit a node (standard page), and try to save it, the menu disappears. Not all node's are like this, only the ones that uses a field group of heatmaps, probably a custom field group (legacy).
System specs are:
CentOS 6.6
Apache 2.2
Mysql 5.5
Php 7
At first, I thought it was a bug in Drupal 7, and I tried solutions as Menu items disappearing in Drupal 7. But the suggested solutions didn't work. So I started to suspect post_max_size or memory_limit, because the form with the custom field grows very large when it uses the field or the field group. So I've maxed the memory settings and it looks good but is still not working.
The field group array tends to be very large and I tried to find some info about nestling level too big in a post but found no hints.
The post size is:
post_max_size in bytes = 536870912
post CONTENT_LENGTH = 1020347
The field group contains Heatmaps with Geolocations and endless of data:
[field_heatmap_data] => Array
(
[und] => Array
(
[0] => Array
(
[tablefield] => Array
(
[cell_0_0] => X
[cell_0_1] => Y
[cell_0_2] => Plastic
[cell_0_3] => Paper
[cell_0_4] => Glass
[cell_0_5] => Metal
[cell_0_6] => Organiskt
[cell_0_7] =>
[cell_0_8] =>
[cell_0_9] => Other
[cell_1_0] => 14.1741233638
[cell_1_1] => 57.7797089972
[cell_1_2] => 0
[cell_1_3] => 0
[cell_1_4] =>
[cell_1_5] =>
[cell_1_6] =>
[cell_1_7] => 1
[cell_1_8] =>
[cell_1_9] => 2
[cell_2_0] => 14.1784435935
[cell_2_1] => 57.7797106709
[cell_2_2] => 0
[cell_2_3] => 0
[cell_2_4] =>
[cell_2_5] =>
[cell_2_6] =>
[cell_2_7] =>
[cell_2_8] =>
[cell_2_9] =>
[cell_3_0] => 14.1656472109
[cell_3_1] => 57.7831198751
[cell_3_2] => 1
[cell_3_3] => 2
[cell_3_4] => 1
[cell_3_5] => 1
[cell_3_6] =>
[cell_3_7] =>
[cell_3_8] =>
[cell_3_9] =>
[cell_4_0] => 14.1753179083
[cell_4_1] => 57.7826699822
[cell_4_2] => 0
[cell_4_3] => 5
[cell_4_4] =>
[cell_4_5] => 3
[cell_4_6] =>
[cell_4_7] => 9
[cell_4_8] => 4
[cell_4_9] =>
[cell_5_0] => 14.1602465906
[cell_5_1] => 57.7824661754
[cell_5_2] => 2
[cell_5_3] => 0
[cell_5_4] => 1
[cell_5_5] =>
[cell_5_6] =>
[cell_5_7] => 4
[cell_5_8] =>
[cell_5_9] => 1
[cell_6_0] => 14.1552312791
[cell_6_1] => 57.7788985858
[cell_6_2] => 0
[cell_6_3] => 1
[cell_6_4] =>
[cell_6_5] => 1
[cell_6_6] =>
[cell_6_7] => 4
[cell_6_8] =>
[cell_6_9] =>
[cell_7_0] => 14.1631063952
[cell_7_1] => 57.7813178687
[cell_7_2] => 1
[cell_7_3] => 0
[cell_7_4] =>
[cell_7_5] =>
[cell_7_6] =>
[cell_7_7] => 2
[cell_7_8] => 3
[cell_7_9] =>
[cell_8_0] => 14.1742044644
[cell_8_1] => 57.7827544419
[cell_8_2] => 0
[cell_8_3] => 0
[cell_8_4] =>
[cell_8_5] =>
[cell_8_6] =>
[cell_8_7] => 4
[cell_8_8] => 1
[cell_8_9] =>
[cell_9_0] => 14.157952438
[cell_9_1] => 57.7818974962
[cell_9_2] => 2
[cell_9_3] => 4
[cell_9_4] => 5
[cell_9_5] => 1
[cell_9_6] =>
[cell_9_7] => 8
[cell_9_8] => 2
[cell_9_9] =>
[cell_10_0] => 14.1706946744
[cell_10_1] => 57.7815507326
[cell_10_2] => 0
[cell_10_3] => 0
[cell_10_4] =>
And so on....
So I've figured out that there is a flaw in the architecture of the node because it cant clearly not handle that much data in a field group and should been handled as an separate node, but since this is a legacy project I don't want to mess things up.
If I var_dump the $_POST variable on different pages when editing, I can clearly see that the $_POST variable stops after the $_POST['field_heatmap'] element where there is data, while the pages that doesn't contain data in that field group the $_POST array continues after the $_POST['field_heatmap'] element.
So my question is, should I continue to try to find a bug in Drupal or should I investigate further some php settings (Or maybe apache). I've tried debugging with cachegrind but can't find any unusual. Or any hints are greatly appreciated!

Answer 1

Finally! The max_input_vars was set to 1000
Changed it to max_input_vars = 10000 and it worked!