> Hi people,

[...]

> I'm not aiming for a "yeah, nice, we'll merge it" on this, but rather
> for suggestions whether it's worth anyones time to pursue this further.

This is interesting, there might be a good outcome of this diff
eventually. However as of now:
- you have removed the bunch of code which tries to make sure processes
  do not hop between cpus unless there is a gain in doing so, on MP
  kernels. Did you try your diff on a MP kernel?
- non-tabbed indent is evil. And makes the diff harder to read.
- I see many locks removed in there, and moving information to the proc
  structure does not explain all of them. This gives a bad gut feeling
  about the behaviour of this on MP kernels. A really bad gut feeling.
- you have changed the roundrobin duration from (hz / 10 to (hz / 100).
  However, this computation yields zero on platforms where hz < 100,
  which is not a good idea. The only assumptions you can make about hz
  is that 50 <= hz <= 1024.
- you removed the enforcement of RLIMIT_CPU. No way. Over my dead body.
- I also don't really like switching from NQS run queues to a single
  one. I understand you need this to be able to compare the deadlines
  with only one queue walk, but this can become expensive with many
  processes in the runqueue...
- your priority computation are unexplained magic. What does 20 mean?
  Shouldn't at least one of them be derived from `hz'? Why << 1 versus
  << 5? Are you sure the values you are computed are always within the
  bounds you are expecting? Why isn't there any comment about these
  computations?

Miod

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