Re: software interrupts & scheduling oddities

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> Maybe this has happened to you: you tune your NetBSD router for
> fastest packet-forwarding speed.  Presented with a peak packet load,
> [...] the user interface doesn't get any CPU cycles.  [...]  [I]f
> there is any software interrupt pending, then it will run before any
> user process gets a timeslice.  So if the softint rate is really
> high, then userland will scarcely ever run.  Or that is my current
> understanding.  Is it incorrect?

"No", I think.  At least, that's how I'd expect it to work, and I've
occasionally seen behaviour close enough to that to make me think it's
reasonably accurate.

I find your discovery about changing a user process's priority making a
difference surprising.

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