I'm using PHP APC on production servers of a web service with 10M's hits/day successfuly for a long time.
I'm considering offloading much more data to the APC local cache.
Theoretically it looks to me that since APC call is mainly a local memory access. It should not become an issue to call it 10,000s of times/sec. As far as I can tell its limits can be in the memory size but as long as the server has free CPU it should not have performance or corruption issues at high rates.
Is there any limit I'm not aware of that might prevent me from using APC's local object cache in very high rate on app server (ubuntu).