PHP APC Cache Does Not Persist Any Variables

Question

I've got to be missing something obvious. My APC is installed correctly and showing up in phpinfo() just fine. I'm currently running php 5.4.20 with APC 3.1.13 on apache. It is a cpanel install so keep that in mind as well.

The main problem is that the cache is working, but only for the duration of the page load. if I run

<?php
    apc_store('foo', 'bar');
    echo apc_fetch('foo');
?>

It will echo out the variable, but if I comment out apc_store and run the code again, nothing shows up and var_dump shows boolean(false);

I've tried this code also in case I was doing something dumb, and this does not work also. It always shows "str not found from cache...saving"

// Check if str found from cache
    if (apc_exists('str')) {
        // Print str from cache
        echo "str from cache: ", apc_fetch('str'), "<br />";
        // Clear cache
        apc_clear_cache('user');
        // Try to fetch str again
        echo "str from cache, after user cache is cleared: ", "<br />";
        var_dump(apc_fetch('str'));
    }
    else {
        // Save str to cache and set ttl 120 seconds
        echo 'str not found from cache...saving', "<br />";
        $str = "This is just test";
        apc_store('str', $str, 120);
    }

My apc config is as follows...

apc

APC Support => disabled
Version => 3.1.13
APC Debugging => Disabled
MMAP Support => Enabled
MMAP File Mask =>  
Locking type => pthread read/write Locks
Serialization Support => broken
Revision => $Revision: 327136 $
Build Date => Oct 17 2013 16:47:57

Directive => Local Value => Master Value
apc.cache_by_default => Off => Off
apc.canonicalize => On => On
apc.coredump_unmap => Off => Off
apc.enable_cli => Off => Off
apc.enabled => On => On
apc.file_md5 => Off => Off
apc.file_update_protection => 2 => 2
apc.filters => no value => no value
apc.gc_ttl => 3600 => 3600
apc.include_once_override => Off => Off
apc.lazy_classes => Off => Off
apc.lazy_functions => Off => Off
apc.max_file_size => 1M => 1M
apc.mmap_file_mask => no value => no value
apc.num_files_hint => 1000 => 1000
apc.preload_path => no value => no value
apc.report_autofilter => Off => Off
apc.rfc1867 => Off => Off
apc.rfc1867_freq => 0 => 0
apc.rfc1867_name => APC_UPLOAD_PROGRESS => APC_UPLOAD_PROGRESS
apc.rfc1867_prefix => upload_ => upload_
apc.rfc1867_ttl => 3600 => 3600
apc.serializer => default => default
apc.shm_segments => 1 => 1
apc.shm_size => 512 => 512
apc.shm_strings_buffer => 4M => 4M
apc.slam_defense => Off => Off
apc.stat => On => On
apc.stat_ctime => Off => Off
apc.ttl => 0 => 0
apc.use_request_time => On => On
apc.user_entries_hint => 4096 => 4096
apc.user_ttl => 0 => 0
apc.write_lock => On => On

I must be missing something obvious..... any help is appreciated. TIA

EDIT

So I checked to see if it apc was working properly on the prod server that has apc already installed on it. It in fact is working as it should be. So I ran php_sapi_name() and on the prod server it is apache2handler and on the dev server (the one I'm currently working with), it is using cgi-fcgi, which is probably the cause for the problem. Since I'm using cPanel I should be able to simply change the PHP "Handler" from suPHP to maybe DSO and it should work after that. The prod server doesn't use cpanel, just good old fashion....er.....non-cPanel stuff to make it work.

Answer 1

I found this thread that answered my question. The root problem was that I was running under CGI-FCGI when I needed be be under DSO/mod_php to run APC properly. Changing that on Cpanel was a beast because the apc.so extension caused the part when you change the php handler to fail....yar.

Answer 2

You'll need to use the APC web interface to debug this issue.

Find a file called apc.php

find / -name apc.php

Now copy this to you www/ folder and load it up in the browser.

(Here's an example of what it looks like: http://andrewdunkle.com/apc.php )

Now, retry your script and check that the variable has been stored properly and has a long expiry date. Also test to see if the system cache appears to get reset on each page load. (APC.php or your other scripts.)

Finally, try switching from worker to prefork in apache. (Or the other way around if you use prefork)