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SubjectRe: Process time measurement too optimistic
On Wed, 8 Jul 1998, Pavel Machek wrote:

> Linux currently charges processes for time at end of timeslice. That


> means that if process wakes because of timer and finishes its
> processing before end of jiffie, no time is charged to him.
> It is possible to exploit this: I have code which eats ~50% of system
> time, still, no time is charged to him. (This is partly dangerous
> because scheduling strategy depends on same times.)

The patch looks good, but I propose we try first what
impact it will have on interactive and multimedia

These tasks depend on the fact that their CPU time is
being charged to background simulations...
Besides, I wonder what would happen if your exploit is
being run on an already loaded machine? It'll probably
be charged for it's CPU time like all other processes.

In short: a good patch, but we should test it
thoroughly for it's impact on responsiveness.

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