Subject: PPP and flow control
To: None <current-users@NetBSD.ORG>
From: Mike Long <>
List: current-users
Date: 01/17/1996 14:50:14
I'm still having problems sending data over my PPP link.  I can
receive data or send *small* amounts of data without difficulty
(e.g. sup works); but any attempt to send a chunk of data over a
certain limit fails.  The only possible explanation I think likely is
that flow control is broken.  I am running an i386 -current system; my
PPP link runs on my 14.4kbps modem.

I experimented with ping's -s flag last night.  While pinging a
machine 3 hops away over a PPP link:

64 byte packets: 0% failure
128 byte packets: 0% failure
256 byte packets: 0% failure
384 byte packets: 38% failure
512 byte packets: 100% failure

Anything over 512 bytes also has 100% failure.

I first ran into trouble after I switched from gcc 2.4.5 to 2.7.2, but
my current kernel was built with -fno-strength-reduce.

Can anyone give me any pointers as to how I can diagnose and debug
this problem?
Mike Long <> 
VLSI Design Engineer         finger for PGP public key
Analog Devices, CPD Division          CCBF225E7D3F7ECB2C8F7ABB15D9BE7B
Norwood, MA 02062 USA       (eq (opinion 'ADI) (opinion 'mike)) -> nil