Re: This is [Re:] How to improve the quality of the kernel[?].

Linus Torvalds
2007-06-19T17:06:51Z

On Tue, 19 Jun 2007, Oleg Verych wrote:
>
> I'm proposing kind of smart tracking, summarized before. I'm not an
> idealist, doing manual work. Making tools -- is what i've picked up from
> one of your mails. Thus hope of having more opinions on that.

Don't get me wrong, I wasn't actually responing to you personally, I was
actually responding mostly to the tone of this thread.

So I was responding to things like the example from Bartlomiej about
missed opportunity for taking developer review into account (and btw, I
think a little public shaming might not be a bad idea - I believe more in
*social* rules than in *technical* rules), and I'm responding to some of
the commentary by Adrian and others about "no regressions *ever*".

These are things we can *wish* for. But the fact that we migth wish for
them doesn't actually mean that they are really good ideas to aim for in
practice.

Let me put it another way: a few weeks ago there was this big news story
in the New York Times about how "forgetting" is a very essential part
about remembering, and people passed this around as if it was a big
revelation. People think that people with good memories have a "good
thing".

And personally, I was like "Duh".

Good memory is not about remembering everything. Good memory is about
forgetting the irrelevant, so that the important stuff stands out and you
*can* remember it. But the big deal is that yes, you have to forget stuff,
and that means that you *will* miss details - but you'll hopefully miss
the stuff you don't care for. The keyword being "hopefully". It works most
of the time, but we all know we've sometimes been able to forget a detail
that turned out to be crucial after all.

So the *stupid* response to that is "we should remember everything". It
misses the point. Yes, we sometimes forget even important details, but
it's *so* important to forget details, that the fact that our brains
occasionally forget things we later ended up needing is still *much*
preferable to trying to remember everything.

The same tends to be true of bug hunting, and regression tracking.

There's a lot of "noise" there. We'll never get perfect, and I'll argue
that if we don't have a system that tries to actively *remove* noise,
we'll just be overwhelmed. But that _inevitably_ means that sometimes
there was actually a signal in the noise that we ended up removing,
because nobody saw it as anything but noise.

So I think people should concentrate on turning "noise" into "clear
signal", but at the same time remember that that inevitably is a "lossy"
transformation, and just accept the fact that it will mean that we
occasionally make "mistakes".

This is why I've been advocating bugzilla "forget" stuff, for example. I
tend to see bugzilla as a place where noise accumulates, rather than a
place where noise is made into a signal.

Which gets my to the real issue I have: the notion of having a process for
_tracking_ all the information is actually totally counter-productive, if
a big part of the process isn't also about throwing noise away.

We don't want to "save" all the crud. I don't want "smart tracking" to
keep track of everything. I want "smart forgetting", so that we are only
left with the major signal - the stuff that matters.

Linus