I'm using squid-3.1.16 on FreeBSD 8.2/amd64 running on localhost. I've noticed that some TCP_HITs are loading very slowly. I've tested this in Opera, Firefox, wget and fetch. Normal TCP_HITs are too fast for wget to meter, but the slows ones are 2kB/s to 30kB/s, mostly around 5kB/s. It's a bit awkward to debug because restarting squid can re-randomize which urls are slow. I've tried rebuilding the port with default options and paring-down squid.conf to a bare minimum. The only thing that seems to make a difference is the cache type. I've seen it happen with aufs and diskd, but since I switched to plain ufs, I haven't seen a single slow TCP_HIT.
