Ensure ServicePoint manager is configured w/consistent defaults wrt to other SDK's HTTP libs

https://msdn.microsoft.com/en-us/library/system.net.servicepointmanager%28v=vs.110%29.aspx

https://msdn.microsoft.com/en-us/library/system.net.servicepoint%28v=vs.110%29.aspx

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"I’ve been working on a CBSE for a United POC and it seems they hit a limit -> the java sdk right now opens 1 connection per query node, which means that if they have 3 query nodes but 5 threads issuing queries, they get stuck in the pipe. Increasing the pool manually is doable, and this is what I told they should do, but I wondered if we should provide a saner default without opening too many sockets in advance.

Looking at other connection pool recommendations it seems that for us the obvious choice would be to recommend:

max parallel user queries = number of nodes * sockets per node

The problem is we don’t know the left side of the equation :/

I’ve asked colm and he suggested the overhead for connections is not super high in the query engine, so we might get away with opening 5 or 10 per node by default.

I think it is hard to generalize since every customer deployment is different.
Michael"