FWIW, I had the same problem when I switched to AR sessions. After
researching and finding many suggested solutions, I found one that
worked for me. I discovered that I was storing some large objects in
my sessions. I changed my technique to only store the object ID of the
larger objects and my "dropped connections" problem ceased. Of course
there is the added overhead of having to "re-find" the object as
needed, but for me at least this was a minor inconvenience. Anyway, my
persisted session data hovers around 300 bytes.