Hi "balance source" is more affinity than persistence, which means that you might be redirected to an other server sometime. To be very efficient, source balancing needs a very large scope of source IPs. You can try mixing balance source with "hash-type consistent" to try to avoid your client to switch from a server to an other one.
Since you're doing long polling I would recommend balance leastconn to balance better te load. If you really need persistence, then you'll have to use either "cookie insert" or "cookie prefix". cheers
