Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]

Davide Libenzi
2007-04-17T07:27:58Z

On Tue, 17 Apr 2007, William Lee Irwin III wrote:

> On Mon, Apr 16, 2007 at 11:50:03PM -0700, Davide Libenzi wrote:
> > I would suggest to thoroughly test all your alternatives before deciding.
> > Some code and design may look very good and small at the beginning, but
> > when you start patching it to cover all the dark spots, you effectively
> > end up with another thing (in both design and code footprint).
> > About O(1), I never thought it was a must (besides a good marketing
> > material), and O(log(N)) *may* be just fine (to be verified, of course).
>
> The trouble with thorough testing right now is that no one agrees on
> what the tests should be and a number of the testcases are not in great
> shape. An agreed-upon set of testcases for basic correctness should be
> devised and the implementations of those testcases need to be
> maintainable code and the tests set up for automated testing and
> changing their parameters without recompiling via command-line options.
>
> Once there's a standard regression test suite for correctness, one
> needs to be devised for performance, including interactive performance.
> The primary difficulty I see along these lines is finding a way to
> automate tests of graphics and input device response performance. Others,
> like how deterministically priorities are respected over progressively
> smaller time intervals and noninteractive workload performance are
> nowhere near as difficult to arrange and in many cases already exist.
> Just reuse SDET, AIM7/AIM9, OAST, contest, interbench, et al.

What I meant was, that the rules (requirements and associated test cases)
for this new Scheduler Amazing Race should be set forward, and not kept a
moving target to fit&follow one or the other implementation.

- Davide