Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!nrl-cmf!mailrus!umix!honey
From: honey@umix.cc.umich.edu (Peter Honeyman)
Newsgroups: comp.dcom.modems
Subject: Re: YATB
Message-ID: <3838@umix.cc.umich.edu>
Date: 12 Mar 88 06:02:59 GMT
References: <17965@oliveb.olivetti.com>
Reply-To: honey@citi.umich.edu (Peter Honeyman)
Organization: Center for Information Technology Integration, Univ of Michigan
Lines: 14
Keywords: techdoc Telebit questions
UUCP-Path: {uunet,rutgers}!umix!honey


if the wire is slower than the host, windowing is a clear win.  but
here, the wire is faster than the host, usually a lot faster.  the
modem immediately fills the window, whatever its size.  thereafter, the
modem sees a window of one -- host acks, modem sends a packet to fill
the window.

your point about context switches is well taken -- it depends on the
scheduler's behavior when the host calls write(ack).  you can probably
convince me that a window of two is worthwhile, but i don't see this
argument extending to anywhere near seven.

someone should run an experiment here.  (i can't, because i don't have
a fast computer with a serial board.)

	peter