Why would apc_store() return false?

Question

The documentation on php.net is very spotty about causes of failure for APC writes. What kind of scenarios would cause a call to apc_store() to fail?

There's plenty of disk space available, and the failures are spotty. Sometimes the store operation will succeed and sometimes it'll fail.

score 55 · Answer 1 · answered Jan 26 '10 at 19:41

55

For php cli it needs to be enabled with another option: apc.enable_cli=On

In my situation it was working when running from a webbrowser, but not when executing the same stuff with php cli.

answered Jan 26 '10 at 19:41

Kees van Dieren

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You can enable this on the commandline with `php -d apc.enable_cli=1` – cbednarski Jan 05 '13 at 02:13
If you test your code with PHPUnit and you use APC variable storage then turn this sucker on. It took me way too long to figure this out. – Sverri M. Olsen Mar 11 '13 at 03:32
@Sverri: hmm nice.. but how can i turn this on for just this specific command? e.g. in phpunit.xml.dist, or as a commandline param for phpunit? – donquixote Jul 18 '13 at 19:52
ok, it works if i run php -d apc.enable_cli=1 /home/thisisme/pear/bin/phpunit, instead of directly running phpunit – donquixote Jul 18 '13 at 19:54
Why is this the default behavior? This should be stated cleary in the documentation. – Chibueze Opata Aug 25 '20 at 20:02

score 10 · Answer 2 · answered Dec 20 '11 at 16:09

I had exactly the same situation.

I migrated my code from using Cron Jobs, to using Gearman Workers, which were managed through supervisord.

Everything Broke. I couldn't ever get caches to work through APC, and had to revert back to using filebase caching.

Eventually I figured out that when I was using cron jobs, I would load each page via wget, rather than command line. This difference, meant that supervisord, which would load my PHP scripts via command line, wouldn't work, because by default APC will not work through command line.

The fix....

apc.enable_cli=On

score 6 · Accepted Answer · answered Nov 03 '09 at 21:27

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out of memory (allocated memory for apc, that is)

answered Nov 03 '09 at 21:27

Nir Levy

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score 4 · Answer 4 · answered May 06 '10 at 02:58

this asinine (and closed, for some reason) bug was my problem:

http://pecl.php.net/bugs/bug.php?id=16814

has to roll back to apc version 3.1.2 to get apc to work. no fiddling with apc settings in php.ini helped (i'm on mac os 10.5, using apache 2, php 5.3).

for me, this test script showed 3 "trues" for 3.1.2 and true/false/true for 3.1.3p1

var_dump( apc_store('test', 'one') ); var_dump( apc_store('test', 'two') ); var_dump( apc_store('diff', 'thr') );

score 2 · Answer 5 · answered Jan 26 '10 at 19:51

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http://php.net/manual/en/apc.configuration.php

the apc.ttl and apc.user_ttl settings on php.ini:

Leaving this at zero means that APC's cache could potentially fill up with stale entries while newer entries won't be cached.

answered Jan 26 '10 at 19:51

byterussian

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score 1 · Answer 6 · answered Nov 03 '09 at 20:50

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Out of disk space or permission denied to the storage directory?

answered Nov 03 '09 at 20:50

Greg

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apc_store() stores data in memory. Not on disk. – Frank Farmer Nov 19 '09 at 21:30

score 1 · Answer 7 · answered Nov 03 '09 at 21:04

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In addition to what Greg said, I'd add that a configuration error could cause this.

answered Nov 03 '09 at 21:04

Tom

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score 1 · Answer 8 · answered Aug 02 '11 at 09:48

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There's a bug in the version installed with ubuntu 10.04 and debian stable. If you replace the package with this version: http://packages.debian.org/sid/php-apc (3.1.7) it works as it should.

answered Aug 02 '11 at 09:48

jw01

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score 0 · Answer 9 · answered Sep 14 '10 at 18:27

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apc_store will fail if that specific key already exists and you are trying to write again to it before the TTL expires. Therefore you can pretty much ignore the return false because it really did fail but the cache is still there. If you want to get around this, start using apc_add instead. http://php.net/manual/en/function.apc-add.php

answered Sep 14 '10 at 18:27

ty91011

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Thats wrong: `apc_store()` overwrites existing keys without failing (--> it returns `true`). `apc_add()` is the one, that _really_ fails on duplicate keys (as the name suggests) – KingCrunch Jan 09 '13 at 22:38

Why would apc_store() return false?

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