Re: SMP Scheduling

Horst von Brand (vonbrand@sleipnir.valparaiso.cl)
Sun, 08 Aug 1999 21:28:50 -0400


Peter Waltenberg <peterw@dascom.com> said:
[...]

> Under 2.0 if you ran a CPU hog it'd pretty well stick to one CPU.

How is that an improvement?

> I.e. if you had xosview running you'd see one CPU at 100%, the other mostly
> idle. If there was a load burst, it might move to the other CPU, but that was
> pretty unusual.

> Under 2.2 you see that one CPU hog hopping CPU's and at regular intervals.
> Using xosview to track load what you see is a picket fence effect.
> And there are more than "3 processes" running, more like 80 on my machine,
> so running xosview alone shouldn't be enough to force this to happen and if
> it were, the other processes should be introducing enough noise to make the
> CPU swapping more erratic.

If you have that many processes running, your hog will have its state at
the CPU flushed anyway, so the CPU selected is irrelevant.

> This does seem to be "wrong", not so much that the process is changing CPU's,
> thats reasonable, but the fact that it's doing it with such regularity
> now.

File it under "random trivia" then ;-)

-- 
Horst von Brand                             vonbrand@sleipnir.valparaiso.cl
Casilla 9G, Viņa del Mar, Chile                               +56 32 672616

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