I don't think increasing cwnd is always the best idea. Have you considered caching the value per IP address and reusing the last probed value when initiating a

I don't think increasing cwnd is always the best idea. Have you considered caching the value per IP address and reusing the last probed value when initiating a new connection to the same host? I think this would get similar results but be safer. I did some limited testing of this approach back in 2000 when I founded a MP3 server startup. I think the only reason cwnd has not been cached historically is that it's done in kernel mode, but on modern machines, it could make sense with the proper cache expiration interval.