Subject: Re: Slow wi0 ftp transfers after kernel upgrade?
To: None <email@example.com>
From: David Young <firstname.lastname@example.org>
Date: 03/01/2003 22:39:59
On Sun, Mar 02, 2003 at 12:33:39PM +1100, Paul Ripke wrote:
> I upgraded my kernel (for a variety of reasons) from 20030128 sources
> up to 20030218, then
> after discovering the problem, up to 20030301, in case it had been
Between 1/28 and 2/18, it does not look to me like anything changed
> BTW: I've also noticed that my wi0 appears to be asymmetric... I get
> approx 180 KB/s in one
> direction (NetBSD sending) and 500+ KB/s in the other.
In Host AP mode, NetBSD does the WEP encryption for transmission.
Perhaps that explains the asymmetry?
> tcpdump shows 0.6 - 1.0 second pauses, which looks like a timeout to
> me. 192.168.254.130 is
> the laptop, 192.168.254.129 is the NetBSD box.
I do not know what could explain the pauses. Does wi0 log anything during
the pauses? You might get to the bottom of this by running in debugging
mode. Add IEEE80211_DEBUG and WI_DEBUG to your kernel config and use
ddb to bump up wi_debug and ieee80211_debug.
> 2 Mbit sounds about right. What happened to DS11?
I don't know why it has adapted to 2Mb/s.
BTW, in Host AP mode, the Prism firmware accepts per-packet TX rates, but
wi(4) does not take advantage. It would be nice if somebody would program
a rate algorithm for the IEEE802.11 framework, especially since this will
be necessary for the "dumber" 802.11 cards coming to market. Lucent has
a technical report on rate adaptation which I can scare up for anybody
who is interested.
David Young OJC Technologies
email@example.com Engineering from the Right Brain
Urbana, IL * (217) 278-3933