PHP Memory exceeded while writing to array in a loop - php

Question

I need to update a value in an array inside a loop. Normally this works fine, but something about this loop is causing the memory to max out.
while ($watering_window['total_run_time'] > $water_window_total)
{
foreach ($master_schedule as &$_ms)
{
$current_soak_time = $_ms['between_starts'] - $_ms['total_run_time'];
if ($current_soak_time > 0)
{
$new_soak_time = ceil($current_soak_time * 0.9);
$_ms['between_starts'] = $_ms['total_run_time'] + $new_soak_time;
$watering_window['total_run_time'] -= $current_soak_time - $new_soak_time;
}
}
}
Something about writing to $_ms['between_starts'] (an existing key) is causing the memory problem. If I change it to write a NEW key (like $_ms['between_starts_new'], no memory problem. I also tried writing a constant value to it (instead of something mathy) and it still timed out.

Answer 1

You'll need to increase the memory_limit.
Add the following at the top of your php script:
<?php
ini_set('memory_limit','256M');
...
Adjust the value according to your needs.

Answer 2

Try unsetting the key that is causing the problem before you set it.
foreach ($master_schedule as &$_ms)
{
$current_soak_time = $_ms['between_starts'] - $_ms['total_run_time'];
if ($current_soak_time > 0)
{
$new_soak_time = ceil($current_soak_time * 0.9);
unset($master_schedule['between_starts']);
$_ms['between_starts'] = $_ms['total_run_time'] + $new_soak_time;
$watering_window['total_run_time'] -= $current_soak_time - $new_soak_time;
}
}