setsockopt takes the value I set for SO_SNDBUF doubles it and use that for the socket size under linux-2.2.17 and linux-2.4.0. I don't see this behavioral on Unicos(CRAYS), Irix, BSDI, SunOS and AIX. I working around the problem by using 1/2 the value that I would use on any other Unix system. The reason this is important is on long distance transfers the send and receive window shuld be set to RTT(round trip time)*BW(Maxium bandwidth) between the two sites. Any large value can, and does, cause tail dropping. A smaller value and you never get the maxium bandwidth. Could some one please fix or at least document it in the setsockopt man page. Bill Jones - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org
