We recently replaced memcache with redis as our cache storage solution backing a Rails web app.
It works fine for a period of time, but after, say a couple of weeks, it will silently stop caching. No exceptions are raised by Rails, but it seems that every cache request is a miss. Rebooting the instance returns everything back to normal.
What is the best way to troubleshoot this? Are there any config settings that are the likely culprit?