I use both.
I have used Linode for 9 or 10 years.
I think they are comparable.
I am going to try Leaseweb when I have time -- their pricing for small VPS is very good -- have to see if there are any issues ...
I think you have PHP code issues if you are exceeding your resources. error_log is a PHP error log name?
you might get some of the script errors in you use the php cli output at the terminal
Code:
cd path/
cd php <script name>.php
you may need to install php cli