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So I have been using memcached to cache lots of data that was the result of queries to the database. Everything left at default, and on average I stored < 40MB in memcache. I used memcache.php to monitor that. Then I decided to switch over to APC and cache things locally because I really did not need memcache (to avoid the TCP overhead?). Then things got big, and I started seeing lots of fragmentation issues. I have a server with 16GB of RAM, and there is plenty to go around, so I assigned APC 2GB. After about 6 hours it filled up to 1.1GB. I think it is getting close to caching everything it can possibly cache. That's a huge difference from what memcache was storing (< 40MB). Not to mention the APC graph shows a whole lot of fragmentation and it is continuing to grow. I'm not sure if this is a problem or not?

Here is a screenshot of what APC.php is giving me:

Some other notes: apc.gc_ttl = 0; apc.stat = 0;

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It has been a few years since I touched APC but from what I recall from my reading there is always some level of fragmentation(well we always had some fragmentation), even with the TTL set to 0. If you are not seeing any performance issues with your system and the fragmentation is sitting around 5 to 7 % then I do not think it is a problem.

Granted more than happy to be shot down in flames on this as I stated it has been a few years since I used APC.

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