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TCP RTO actual value

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linux-howto

http://www.linuxforums.org – Hi, I've been experiencing problems with multiple TCP connections when initially trying to create >3 connections, it seems like the ARP request->reply makes some of the connections do a retry with the default RTO value (3000 ms). This only occurs with the first connection attempt. Once the mac address is in the ARP tables, no delay is noticeable. I am trying to lower this TO value, and found that it's primary initialized as 3000 ms (2.6.32; ./include/net/tcp.h: 130) but could not find if it is affected by any kernel tunable. It seems like some tunable values should affect TO value (tcp_frto / tcp_frto_response), but they don't ease my problem. Can you advise if there's any way to decrease the amount of time spend before re-trying to send SYN, in case MAC record was not found in ARP table ? Thanks a lot, Shay (HowTos)