yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi) writes:

>> I've just recently discovered something interesting with Xen3 that
>> might be related: if the dom0 is running something that spins the CPU
>> (like "perl -e '1 while 1'" or "yes > /dev/null") the NetBSD domU will
>> not be run at all; it won't respond to the console nor to network
>> traffic, and its timer event handler won't be called.  A Linux domU
>> doesn't appear to have the same problem.
>
> it's a characteristic of the default setting of sedf scheduler.
> are you sure it doesn't happen for linux domU?

The Linux domU is definitely affected, but it's still able to answer
pings (if a bit slowly), while the NetBSD one doesn't answer any until
the dom0 stops hogging the CPU.

However, I see what you mean about the default scheduling parameters,
I think -- giving the domU a nonzero minimum timeslice fixes this.

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