Re: [2.4.17/18pre] VM and swap - it's really unusable

[Martin Knoblauch]

> Re: [2.4.17/18pre] VM and swap - it's really unusable
> 
> 
> This is getting silly ... feeback like "ll is better than PK", "feels
> smooth", "is reponsive", "my kernel
> compile is faster than yours", etc. is not getting us any closer to the
> "how" of making a better kernel.
> 
> What's the goal? How should SMP and NUMA behave? How is success measured?
> 
> It would be good to be very clear on the ultimate purpose before making
> radical changes. All of
> these changes are dancing around some vague concept of
> reponsiveness...so define it!
>

 OK, just my set of goals/requirements for a usable/production kernel:

- working VM under a broad set of loads. Working means fair/fitting
treatment of cache vs. process memory, no OOM killing processes when
there is plenty memory in "free+buffer+cache", no unnecessary swapping
out of processes if there is plenty of "free+buffer+cache" memory.
- good/great interactive feel. This means no loss of interactivity due
to cache vs. process memory issues. This means no loss of interactivity
due to heavy IO.
- Good enough worst case latency for "amateur" audio/DVD playback.

 What *I* do not need it "hard real-time" with 101% guaranteed response
times.

 What *I* want is to see my goals in the stock kernel, without needing
to apply a weird set of patches :-)

 How we get there I do not care to much. If -aa can solve the VM
problems, fine. If rmap solves them, great. Just bring a working,
maintainable solution in.

 Ditto for LL vs. preempt.

Martin
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