Subject: wip/kismet vs. wi(4): kernel eats CPU
To: None <>
From: Thomas Klausner <>
List: tech-net
Date: 06/11/2006 17:51:08

I recently tried the wip/kismet package with a wi(4) card:

wi0 at pci0 dev 10 function 0: Intersil PRISM2.5 Mini-PCI WLAN (rev. 0x01)
wi0: interrupting at irq 11
wi0: 802.11 address 00:09:5b:2f:0e:76
wi0: using RF:PRISM2.5 MAC:ISL3874A(Mini-PCI)
wi0: Intersil Firmware: Primary (1.0.7), Station (1.3.6)
wi0: 11b rates: 1Mbps 2Mbps 5.5Mbps 11Mbps

AIUI, kismet does channelhopping to find all available networks.
On my Athlon XP 2400 with NetBSD-3.99.18, this made the machine
nearly completely unresponsible since it seemed to spend quite a
lot of time in the kernel (I assume the wi(4) driver).

I was a bit surprised, since I thought that an Athlon XP 2400 would
have quite enough CPU power for this task. I guess that the wi(4)
driver or hardware is not well-suited for the task.

Did anyone else see this?

Is this a bug in the driver, or is it a problem with the hardware?

If it's the latter, what do you recommend as wireless card under NetBSD?