Messages in this thread |  | | Date | Wed, 28 Mar 2012 07:12:43 +0200 | From | Heinz Diehl <> | Subject | Re: [ANNOUNCE] BFS CPU scheduler version 0.420 AKA "Smoking" for linux kernel 3.3.0 |
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On 25.03.2012, Valdis.Kletnieks@vt.edu wrote:
> I'va always wondered what people are using to measure interactivity. Do we have > some hard numbers from scheduler traces, or is it a "feels faster"?
I guess it's a "feels faster", because it's the only thing that counts. Given that there is strong evidence that scheduler A is "faster, more interactive", whatever... than scheduler B, but a controlled trial shows a significantly better "feels faster" experience using scheduler B, I'm quite shure that people would choose scheduler B over A, and that's quite ok. It does what they expect it to do, despite evidence which documents the opposite.
> And if it's a subjective thing, how are people avoiding confirmation bias (where you > decide it feels faster because it's the new kernel and *should* feel faster)?
Confirmation bias is one thing, and it does exist. Surely. So it's up to the user if it wants evidence, or if it's enough that it feels faster. I guess that evidence doesn't really matter for the most of the users as long as they have a positive experience.
> Anybody doing blinded boots, where a random kernel old/new is booted and the > user grades the performance without knowing which one was actually running?
Hey, we could construct a randomized controlled trial on this :-)
> And yes, this can be a real issue - anybody who's been a aysadmin for > a while will have at least one story of scheduling an upgrade, scratching it > at the last minute, and then having users complain about how the upgrade > ruined performance and introduced bugs...
Yep. They who have to do "real work" will rather base it on evidence than trust their own feelings.
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