Re: cat /dev/hdb > /dev/null DoS

[Sven Köhler]

> I did cat /dev/hdb > /dev/null and after a while (5 minutes),
> the system went totally unresponsive:
>
> 1) man top takes 3 minutes to display man page
> 2) Switching between console and X takes also a couple of minutes
> 3) top shows this:
>
> Cpu(s):  1.4% us,  1.4% sy,  0.0% ni,  0.0% id,  0.0% wa, 97.3% hi,  0.0% si

i guess you have DMA enabled on /dev/hdb. I would expect, that the 
system is at least 50% idle

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