Hi all, We have a mystery on Windows, perhaps someone on the list can help us solve it. I've also posted this to Stackoverflow: http://stackoverflow.com/questions/33409749/why-does-tcp-ip-on-windows-take-500-sends-to-warm-up Original thread: http://lists.zeromq.org/pipermail/zeromq-dev/2015-September/029629.html -Pieter