Xref: utzoo comp.unix.xenix:2007 comp.dcom.modems:1740
Path: utzoo!utgpu!water!watmath!clyde!ima!spdcc!dyer
From: dyer@spdcc.COM (Steve Dyer)
Newsgroups: comp.unix.xenix,comp.dcom.modems
Subject: throughput using CTS flow control on a Trailblazer+
Message-ID: <871@spdcc.COM>
Date: 16 Apr 88 18:41:36 GMT
Reply-To: dyer@spdcc.COM (Steve Dyer)
Organization: S.P. Dyer Computer Consulting, Cambridge MA
Lines: 19

I'm using a Telebit Trailblazer+ on one of my dialin ports, fixed at 19.2kb
using hardware flow control (gettydefs has EXTA and CTSFLOW defined).  I'm
finding that effective UUCP throughput ranges between 80-100 bytes per second
when a UUCP neighbor without a Trailblazer dials in at 2400 baud, completely
negating any benefit of the neighbor's >1200 baud speed.  The CTS light seems
to blink on every SD (send data) blink.  People who dial in to this line at
2400 baud also report jerkiness (although this seems to be hidden and not
observable at 1200 baud.)

Note we don't appear to be losing data; the low transfer rate isn't due to
retransmissions, but due to (excessive?) throttling of the output stream.

Any ideas of what to try?

/Steve
-- 
Steve Dyer
dyer@harvard.harvard.edu
dyer@spdcc.COM aka {ihnp4,harvard,husc6,linus,ima,bbn,m2c}!spdcc!dyer