I have noticed (via the APC control panel) that on each refresh
- The hit count rises and falls.
- The hits vs misses values fluctuate wildly, on one view it will be at 99% hits, 1% misses. On the next 30% hits, 70% misses
- Memory usage jumps around erratically.
Now I would expect that these values would only rises until the server or APC is restarted. Can anybody explain what is happening here?
The only explanation I can think of is that as I am running Apache (2.2.15) with CGI-FCGI there are multiple instances of APC running. On each refresh I am seeing the stats for a single instance. This seems to be confirmed by this question:
However, this is from 2009 so I am surprised there isn't a solution for this (assuming one is needed)
For reference by APC config is as follows:
extension=apc.so [apc] apc.cache_by_default=1 # disable by default. apc.enabled = 1 apc.shm_segments = 1 apc.shm_size = 128 apc.max_file_size = 10M apc.stat=1