William L. Jones writes: > 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. You should not half the number you send to the kernel. The kernel is doubling the number you give it because this SO_SNDBUF value also accounts for the size of internal buffer structures used to keep track of the socket send data _as well_ as the data bytes themselves. There have been many threads about this, whether it is good or bad, etc. but the long and short of it is that the behavior is not going to change. > Could some one please fix or at least document it in the setsockopt > man page. I believe Andi Klein did update the man page in the last few months to at least mention something about this. Later, David S. Miller davem@redhat.com - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org
