[2475] in linux-net channel archive
Re: PPP is slow (and so is TCP!) [with fixes]
daemon@ATHENA.MIT.EDU (Tony Nugent)
Fri Apr 12 23:55:44 1996
Date: Sat, 13 Apr 1996 05:05:19 +1000
From: Tony Nugent <tonyn@sctnugen.ppp.gu.edu.au>
To: linux-net@vger.rutgers.edu
Cc: kernel-patch@anime.net
Eric Schenk <schenk@rnode84.cs.toronto.edu> wrote:
> Sender: owner-linux-net@vger.rutgers.edu
(I'm a lurker here. linux-kernel has become just too much to cope
with)-:
> I've spent the last couple of days giving the Linux TCP stack a hard stare,
> and I believe I have fixed a number of problems that have existed for
> quite some time. While I was at it I implemented a basic version
> of the fast retransmit algorithm for single dropped packets.
[munch]
> First, let me address the numerous complaints that since 1.3.73 Linux
> PPP has been had a very bad interactive response, particularly with
> Solaris boxes. (I have been one of those people plagued by this problem,
> which was why I started looking into this stuff in the first place.)
> Now, on to the real bugs. For quite some time (over a year) I have
> noticed that FTP gets from Solaris boxes never achieve full throughput,
> ...
[gobble]
> Second, after I fixed the above problem I found that delayed ACKs
> where not being dealt with correctly. In particular we're
> violating RFC1122 in a couple of places:
> begin 644 tcp_patch.1.3.p87.gz
While I can't verify if what you've done is correct, this all looks
like a lot of excellent detective work.
If the problem has been there for more than a year, the implication is
that it affects the 1.2.x kernels.
This patch is for 1.3.x, but would it be possible (appropriate?) to
attempt to apply your changes to 1.2.13?
Just wondering, as I'm currently maintaining a set of bug-fix patches
for 1.2.13 (see http://trishul.sci.gu.edu.au/~tony/linux/patches.html
and http://www.anime.net/linux/). These patches are going to be
sorted out soon and presented to Linus for his official (or unofficial)
blessing. A fix in the TCP code like what you are proposing would be
likely have a place in there too.
Cheers .
Tony _--_|\
tony@sctnugen.ppp.gu.edu.au / *\ T.Nugent@sct.gu.edu.au
tnugent@cit.gu.edu.au \_.--._/ ae.nugent@qut.edu.au
Brisbane, Queensland v Australia
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is done by children.
