Subject: TCP behavior
To: None <>
From: None <>
List: tech-kern
Date: 01/10/2003 08:46:46
When using a TCP connection against a Windows Client we see the following
behavior:  the window size is negotiated to 64K, the server (NetBSD) dumps a
large buffer (100K+) to the client (MS Windows).  The first two or three
packet transmissions are back-to-back,  (no delay between data packets or ms
windows ack) Windows (microsoft) sends an acknowledge.  NetBSD then holds
off about a millisecond, then begins dumping data again, it gets two or
three packets out and MSWindows sends an ack, again NetBSD holds off a
millisecond and begins transmitting again.  We would hope to see NetBSD dump
near a full window of data to the client before any delays in the
transmission take place.  The MSS is negotiated to 1460.  The application
does a single write for the entire buffer to the TCP socket.  We use
setsockopt to set the rcv & tx buffer sizes to 128K. 

Any help is appreciated,