Re: 2.6 much worse than 2.4 on poor wlan reception

From: Denis Vlasenko
Date: Thu Mar 04 2004 - 16:59:29 EST


On Thursday 04 March 2004 20:01, Thomas Mueller wrote:
> I have big problems with kernel 2.6 and WLAN. Quite often the connection
> interrupts completely, I can't transfer anything for minutes - making
> 2.6 unusable for me :-(

> blade:~# iwconfig eth1
> eth1 IEEE 802.11-DS ESSID:"WLAN" Nickname:"Prism I"
> Mode:Managed Frequency:2.412GHz Access Point:00:60:B3:17:F8:8C
> Bit Rate:11Mb/s Tx-Power=15 dBm Sensitivity:1/3
> Retry min limit:8 RTS thr:off Fragment thr:off
> Encryption key:[ secret ] Security mode:open
> Power Management:off
> Link Quality:1/92 Signal level:-101 dBm Noise level:-149 dBm

I have Prism 2.5 cards. I run them with hostap driver.
Link quality of 1/92 is very bad. You are on the edge
of losing connection. (At least this is the case for
my hardware).

Let's see how much errors do you have. Do this:

# cat /proc/net/wireless /proc/net/dev

On my system wlan1 has "Link Quality:66/92"
(wlan0 is an AP, has no meaningful Link Quality)

Inter-| sta-| Quality | Discarded packets | Missed | WE
face | tus | link level noise | nwid crypt frag retry misc | beacon | 16
wlan0: 0000 0 0 0 0 9178 13 23727 142280 0
wlan1: 0000 66. 195. 156. 0 0 0 3422 309008 0

Inter-| Receive | Transmit
face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed
wlan0:1829928225 2539552 0 80689 0 0 0 0 1966341385 2579089 0 42 0 0 0 0
wlan1:143242367 907236 0 0 0 0 0 0 11481487 74357 0 0 0 0 0 0

So, wlan1: 907236 rx packets, 3422 retries
(and 309008 packets wasn't for me, wrong MAC, I suppose ;) )
What's your numbers?

> There was a break when netio transfered the 2k blocks.
>
> My log is full of entries like this one:
> Mar 1 17:54:12 blade kernel: eth1: New link status: AP Out of Range
> (0004)
> Mar 1 17:54:12 blade kernel: eth1: New link status: AP In Range (0005)
> Mar 1 17:54:16 blade kernel: eth1: New link status: AP Out of Range
> (0004)
> Mar 1 17:54:16 blade kernel: eth1: New link status: AP In Range (0005)
> Mar 1 17:54:19 blade kernel: eth1: New link status: AP Out of Range
> (0004)
> Mar 1 17:54:20 blade kernel: eth1: New link status: AP In Range (0005)
> Mar 1 17:54:22 blade kernel: eth1: New link status: AP Out of Range
> (0004)
>
> Kernel 2.4 works far better in the poor reception situation I have,
> anyone any idea what I could do without moving the AP or laptop?
> When I'm near my AP everything works fine with 2.6 too.

Is your orinoco driver is the same for 2.4 and 2.6?
Maybe 2.6 one has a bit lower max retry count or some such?

> BTW: removing the PCMCIA card when it's in use freezes my system
> completely, that was no problem with 2.4.

No oops? No SysRq?
--
vda

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