From mboxrd@z Thu Jan  1 00:00:00 1970
From: andrey mirtchovski <mirtchov@cpsc.ucalgary.ca>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] drawterm strangeness
In-Reply-To: <599ac5bac00ad3dde089ea36e02bc81e@plan9.bell-labs.com>
Message-ID: <Pine.LNX.4.44.0306061520200.26010-100000@fbsd.cpsc.ucalgary.ca>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Date: Fri,  6 Jun 2003 15:32:07 -0600
Topicbox-Message-UUID: c738041e-eacb-11e9-9e20-41e7f4b1d025

You were completely right -- linux' nagel was delaying it. Apparently the
binary I was using wasn't compiled with TCP_NODELAY. In FreeBSD there's a
sysctl to turn Nagel off, but not in Linsux.

I recompiled drawterm with TCP_NODELAY in and the speed went up to 50mbit/s
with very smooth display of images, scrolling and the like.

Here's a buglet for drawterm if you're interested (compiled on
Linux/RH8.0/2.4.20/gcc3.2):

    - ifdef-ed "#include <linux/tcp.h>" in devip-unix.c (that's where
      TCP_NODELAY is defined now for Linux)

    - mk 'CONF=Linux' would not succeed because of unresolved symbols. It
      needs '-ldl -lpthread' now to compile.

    - interestingly enough mk 'CONF=FreeBSD' works just fine in Linux,
      (apart from the fact that linux/tcp.h needs to be in devip-unix.c)

    - doprint.c:530 -- change to:

            rune = (Rune)va_arg(*arg, unsigned int);

      reason: va_arg() doesn't accept shorts as the second argument anymore.

cheers: andrey

On Fri, 6 Jun 2003, Russ Cox wrote:

> yes but linux might be delaying the responses.
> make sure the devip-unix.c you are using says
> something about TCP_NODELAY.
>