[GRLUG] wifi connection drops under Ubuntu

[peyeps at iserv.net]

For comparison purposes, I am running Ubuntu 9.04 oan  an Aspire One.

When I run iwconfig I get:

wlan0     IEEE 802.11bg  ESSID:"Network_Netgear"
          Mode:Managed  Frequency:2.432 GHz  Access Point: 00:22:3F:A4:95:CE
          Bit Rate=24 Mb/s   Tx-Power=20 dBm
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B
          Power Management:off
          Link Quality=46/100  Signal level:-53 dBm  Noise level=-83 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

I don't see a noise level on your report, but noticed your signal level is
about the same as my noise level.  I assume the difference is due to the
version of Ubuntu you installed.  I refrained from going up to 10, because
I heard some things did not work as well.  I don't know if you want to try
an install of 9.04.  You could try it on a memory stick, and see if that
helps.  (Like a live CD).   The other two things I can think of, I noticed
you are running a much faster network than I am.   The Netgear router I am
using is a relatively because we were having problems with the signal
dropping with the Linksys router we had, with my wife's Macbook.  I think
the Netgear router was something like $35.00.  The cheapest thing to try
at the moment to my mind might be to try the 9.04 on a memory stick.  I've
used nothing but the Ubuntu 9.04 on this netbook.  It did come with XP
pre-installed, and the partition for that still exists, but never booted.


>
> Message: 1
> Date: Thu, 8 Apr 2010 18:19:12 -0400
> From: John-Thomas Richards <jtr at jrichards.org>
> Subject: [GRLUG] wifi connection drops under Ubuntu
> To: grlug at grlug.org
> Message-ID: <20100408221912.GA16797 at jrichards.org>
> Content-Type: text/plain; charset="us-ascii"
>
> I bought an Acer Aspire One for my wife.  It came with Win7 Starter
> Edition.  W7SE is a dog.  I installed Ubuntu (full, not Netbook Remix)
> on it.  It is much snappier than Win7.  However, wifi does not work as
> well under Ubuntu as it does under Win7.  Win7 shows signal strength
> around 85% and Ubuntu (NetworkManager) shows it around 42%.  Googling
> has revealed that these figures may not be accurate.  I am inclined to
> trust them since Win7 never experiences loss of network connectivity
> whereas Ubuntu experiences frequent drops.  I disabled power management
> on the wifi card (thinking that perhaps Ubuntu is mistakenly reducing
> the power to it in an effort to save power).  This does not eliminate
> the loss of connectivity.  I am not sure what else to do, but no matter
> what, I cannot tell my wife to just boot into Windows.  Any ideas?
> --
> john-thomas
> ------
> If the gods listened to the prayers of men, all humankind would quickly
> perish since they constantly pray for many evils to befall one another.
> Epicurus, philosopher (c. 341-270 BCE)
>
>
> ------------------------------
>
>
> root at djr-laptop:~# iwconfig wlan0
> wlan0     IEEE 802.11bgn  ESSID:"boston_celtics"
>           Mode:Managed  Frequency:2.462 GHz  Access Point:
> 00:18:39:B6:9B:2E
>           Bit Rate=54 Mb/s   Tx-Power=20 dBm
>           Retry  long limit:7   RTS thr:-Off   Fragment thr:-Off
>           Encryption key:ECF6-C681-FC
>           Power Management:-Off
>           Link Quality=26/70  Signal level=-84 dBm
>           Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
>           Tx excessive retries:0  Invalid misc:0   Missed beacon:0
>
>> > I disabled power management
>> > on the wifi card (thinking that perhaps Ubuntu is mistakenly reducing
>> > the power to it in an effort to save power). ?This does not eliminate
>> > the loss of connectivity. ?I am not sure what else to do, but no
>> matter
>> > what, I cannot tell my wife to just boot into Windows. ?Any ideas?
>>
>> Watch /var/messages and /var/syslog. There's likely something
>> interesting there.
>
> It just lost connection again.  dmesg shows multiple entries of this:
>
> [ 1927.216729] ath9k: DMA failed to stop in 10 ms AR_CR=0x00000024
> AR_DIAG_SW=0x40000020
>
>> It's also possible that the Aspire One generates more EMI when running
>> Ubuntu's drivers and policies than when running Windows' drivers and
>> policies, based on configuration of the device. It may actually *help*
>> to be more aggressive on power policies for things like your hard disk
>> and CPU speed.
>
> How could Ubuntu's drivers and policies result in more EMI?
> --
> john-thomas
> ------