APC User Cache Key collisions on multiple sites

Question

What's the best option for avoiding key collisions between multiple sites running on the same server using APC for user caching?

I've run into issues where 2 or more sites were using the same cache key and expecting different types of items to be stored under it--one expecting a json string, the other an array, another an object.

Is their a way to segment APC by site?

BTW: I'm using APC with Apache running prefork and mod_php.

I'm a bit confused as to why this was downvoted; it's a reasonable question, and one which I was looking for an answer too as well. I hadn't even thought of server variables (the answer), and it was helpful. On a site where a question asking to test if a number is negative has 300+ votes, I can't understand how this question was downvoted. — Ben
@mazzzzz it looks like a user upvoted it a while back, but SO deleted the user and took away they points which were awarded :/ — Ray

Lawrence Cherone Lawrence Cherone · Accepted Answer · 2012-11-08T14:55:01

Perhaps you could append the server hostname to the key, you could define a constant or create some model for handling your APC:

<?php 
define('APC_HOST_KEY',$_SERVER['HTTP_HOST']);

apc_store(APC_HOST_KEY.'_value_key', $value);
?>

APC User Cache Key collisions on multiple sites

1 Answers