[squid-users] Squid-Cache VS PHP, put some things in perspective

[Amos Jeffries]

On 13/04/22 10:30, Eliezer Croitoru wrote:
> 
> I am looking for adventurous Squid Users which wants to help me test if 
> PHP 7.4+ still possess the same old 5.x STDIN bugs.
> 


Hi Eliezer, Thanks for taking on a re-investingation.


FTR, the old problem was not stdin itself. The issue was that PHP was 
designed with the fundamental assumption that it was used for scripts 
with very short execution times. Implying that all resources used would 
be freed quickly.

This assumption resulted in scripts (like helpers) which need to run for 
very long times having terrible memory and resource consumption side 
effects. Naturally that effect alone compounds badly when Squid attempts 
to run dozens or hundreds of helpers at once.

Later versions (PHP-3/4/5) that I tested had various attempts at 
internal Zend engine controls to limit the memory problems. Based on the 
same assumption though, so they chose to terminate helpers early. Which 
still causes Squid issues. PHP config settings for that Zend timeout 
were unreliable.


AFAIK, That is where we are with knowledge of PHP vs helper usage. 
PHP-6+ have not had any serious testing to check if the language updates 
have improved either resource usage or the Zend timeout/abort behaviour.


HTH
Amos