Date: Fri, 7 Apr 95 10:34:06 EDT From: fcawth@squid.umd.edu (Fred Cawthorne) To: obrien@antares.aero.org (Mike O'Brien) Cc: questions@FreeBSD.org Subject: Re: pppstats shows 5% packet error rate Message-ID: <9504071434.AA09044@squid.umd.edu> In-Reply-To: <95Apr7.015514pdt.111113-2@aero.org>; from "Mike O'Brien" at Apr 7, 95 1:55 am
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> > I'm running 2.0R, with the one-line PPP fix. > > My PPP connection appears to run as it should, but it also shows > about a 5-10% packet error rate. Running pppstats, I can see batches of 7 > or 8 errors happening at a time during, say, an inbound FTP. During > these periods the modem shows as mostly idle. Possibly it's waiting for a > TCP timeout/retransmission. I am running a U.S. Robotics Sportster > modem, 14.4Kb, dialup into an Annex box. I have 16550s in my Pentium 90. > I'm running a Logitech bus mouse and XFree86 3.1.0 at the time. > > These errors and timeouts slow things down. What's the use of > spending the bucks to run at 28.8 if I'm only going to spend most of my > time waiting for TCP (or maybe PPP) timeouts? > I get the same sort of timeouts with my 28.8K modem telnetting through an annex into a FreeBSD box. The server side is FreeBSD2.0, and the client is Snap950210. It seems that sending something (like hitting CR in a telnet session) causes it to stop waiting. It also seems like only things that send a large amount of data in a stream trigger the problem. I can run x clients with very little delays, for example. I haven't tried ftp'ing a file to /dev/null either. There may be something lost somewhere when the disk is writing. I have tried going at 14.4K, turning off compression, etc... and it does the same thing. And I escape the ^S / ^Q and the telnet escape character too. My home machine is a 486/66 with 8 megs ram and an IDE drive running Snap 950210 and my work machine is a Pentium 90 with 32 megs ram and scsi drives. > Is anybody else seeing this? Even suggestions of what to tear > into would be welcome. I am comfortable with banging on kernel source if > I know where to start. > I am going to check to see if anything has changed in pppd or the driver since 2.0. Perhaps a bug was fixed. (or introduced...) I may also just try to install the latest snapshot at home to see if it helps. Fred.
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