🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.os.linux.misc
Article #563

Re: Slow Performance froma "Fast Serial Card"?

#563
From: Chris
Date: Tue, 25 Mar 1997 00:00
50 lines
3166 bytes
Nils Faerber wrote:
> 
> fwtk@niw.cerberus.navy.gov.au wrote:
> : Can anyone offer me some pointers on this one please?
> I hope so ...
> 
> : I am using a Linux box as an Internet gateway for a LAN and some dial-in
> : lines.  The box has two internal 14.4kbps modems and one external 28.8
> : kbps modem.  Two lines are for dialling in and on to dial out to the
> : ISP.
> : If I use one of the 14.4 kbps modems to dial the ISP I get a download
> : speed of around 1000-1300 bytes/sec.  I think this is pretty
> : reasonable.  However, when I try to use the 28.8 kbps modem to dial the
> : ISP (preferable) the download speed drops to between 100-200 bytes/sec!
> : ie, about 10 times SLOWER :-(
> : I think it must be the serial card, but it is a new serial card with
> : 16550 UARTS.  I have tried configuring it at boot time with:
> This sounds like an interrupt conflict to me. More than two serial ports, and
> an internal modem is a serial port, are always difficult (there recently was
> a thread about this somewhere in comp.os.linux.* land). So check your
> interrupt settings. If you use standard settings you will probably have
>  ttyS0 IRQ 4
>  ttyS1 IRQ 3
>  ttyS2 IRQ 4 (!!!)
> Most PC cards are not designed to share interrupts, but it is possible
> though. If you can avoid shared interrupt whereever possible.


You might also want to make sure you're running
'setserial' at boot time.  I've got 4 serial ports,
at IRQ 4, 3, 7, and 11.  Even though they're all
on separate IRQs I was getting miserable results
until I ran setserial set to autoprobe everything
in my /etc/rc.d files (slackware distribution).
Once setserial ran everything was peachy-keen.

-- 
                                   ....... The free UNIX operating
system
Chris Harshman                      `:::'                  ....... 
......
XCC System Administrator             :::  *                  `::.    ::'
harshman@paradigm.uor.edu            ::: .::  .:.::.  .:: .::  `::. :'
http://paradigm.uor.edu/harshman     :::  ::   ::  ::  ::  ::    :::.
909.307.7692                         ::: .::. .::  ::.  `::::. .:'  ::.
                                   ..:::.....................::'  
.::::.
    "Linux - the OS people choose without $200,000,000 in persuasion."
  UNIX is user-friendly.  It's just selective about who its friends are.
Technical Details
Message-ID: <33383F2A.52803703@paradigm.uor.edu>
Path: arc1-ca.pugleaf.net!unknown!not-for-mail
References: <33308CB0.170C@niw.cerberus.navy.gov.au> <5h0noc$1su@asgard.si.sub.de>

Show Full Headers
Complete Article Headers
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 1103af,d120540d33c72067
X-Google-Attributes: gid1103af,public
X-Google-Thread: f9b51,d120540d33c72067
X-Google-Attributes: gidf9b51,public
X-Google-Thread: 10669a,d120540d33c72067
X-Google-Attributes: gid10669a,public
X-Google-Thread: 102983,d120540d33c72067
X-Google-Attributes: gid102983,public
From: Chris <harshman@paradigm.uor.edu>
Subject: Re: Slow Performance froma "Fast Serial Card"?
Date: 1997/03/25
Message-ID: <33383F2A.52803703@paradigm.uor.edu>
X-Deja-AN: 228691746
References: <33308CB0.170C@niw.cerberus.navy.gov.au> <5h0noc$1su@asgard.si.sub.de>
Organization: Enterprise for Economic Excellence
Newsgroups: comp.os.linux.misc,comp.os.linux.networking,comp.os.linux.setup,aus.computers.linux