"... so now I will jiggle things randomly until they unbreak" is not acceptable'

http://thread.gmane.org/gmane.linux.kernel/1126136

by signa11 • 15 years ago

352 126 15 years ago

thread.gmane.org

hobbes2• 15 years ago

Well, that approach worked fine for the evolution of complex life-forms.

redfloatplane• 15 years ago

Yes, but the "we have billions of years to get this right" model generally doesn't apply to software dev. ;)

hobbes2• 15 years ago

Unless you're coding Duke Nukem Forever. ;)

redthrowaway3• 15 years ago

With a 99.9999% failure rate.

apower2• 15 years ago

Why do you think Linux isn't the 0.0001% survived form?

waitwhatwhoa• 15 years ago

this would be "years and years of testing on thousands of machines," no?

vog2• 15 years ago

Once again, a great Linus Torvalds statement! I especially like the last paragraph, which has so much truth in it, and can be applied to small as well as large software projects:

Don't just make random changes. There really are only two acceptable models of development: "think and analyze" or "years and years of testing on thousands of machines". Those two really do work.

masklinn• 15 years ago

To be fair, the second case really is just a matter of fossilized random changes.

NetMonkey• 15 years ago

Linus knows that and says so as well. But that's okay, because that works. Starting down that very same path again without a huge reason to do so would be very painful for any mature product.

lindvall2• 15 years ago

That is correct, but is based on a philosophy that the longer something has been in use, the less chance it has to demonstrate behavior that has not been previously observed — he even explains that in more detail in further posts where he discusses his desire to not cause regressions.

gritzko• 15 years ago

Yep, that's how the evolution works. Understanding stuff is how the progress works.

andrewflnr• 15 years ago

Doesn't that mean that while it's actually happening, it's not, in fact, an acceptable development process?

billswift2• 15 years ago

Or, in slightly different words, "understand it" or "test the hell out of it".

watmough• 15 years ago

I've worked with programmers who also would have argued with Linus, but there's no way I would have been able to be as direct as Linus has.

This definitely struck a chord, though, and I have my own saying for silent retorts:

"It's a computer program, not a #$%^ing Advent calendar."

The point being, I want to see analysis and process, not just the right numbers popping up in the right boxes.

gregschlom4• 15 years ago

Am I mistaken in thinking that in this case, it might also be a cultural/communication problem?

When Yinghai answers:

  We did do the analyzing, and only difference seems to be:
  good one is using 0x80000000
  and bad one is using 0xa0000000.

he clearly didn't understand what Linus meant by "think and analyze".

I don't know the Chinese culture well enough (assuming Yinghai is from China), but I am under the impression that they would emphasize more on results (fix the problem) than on processes (understand why the fix works, in order to be sure we are not breaking something else).

Am I wrong?

vog2• 15 years ago

Indeed, those are cultural differences. However, I don't think those are directly linked to nations. Even within a single country like Germany, I'm observing vastly different approaches to software development.

Also, issues like "Why don't you accept my (seemingly) working patch?" appear quite frequently in a lot of Free Software projects, independently of the nations of the people.

I guess this cultural difference has more to do with professionalism and long-term experience on software projects.

verroq2• 15 years ago

Did you just generalise an entire nation of people based on the internet postings of one person with a Chinese name?

Are you implying the "fix it and get it done with" people don't exist in other nations?

gregschlom4• 15 years ago

Nope, I did the oposite: I already had a generalisation in mind, and used it to try to understand the posting of one persone with a Chinese name.

Mind you, cultural traits of nations are a reality. I'm a Franco/Brazilian guy living in Vietnam, and I have seen it well enough. It doesn't mean that since you're from country X you will do Y, but it helps in understanding general behaviors.

edit: excellent book on this topic: When Cultures Collide, by Richard Lewis

http://www.amazon.com/When-Cultures-Collide-Richard-Lewis/dp...

cdavid• 15 years ago

I don't know about Chinese culture, but I am always amazed that so few people in software engineering actually understand the difference. I think that's the essence of the "being smart and getting things done" thing of Joel Spolsky. Things which would be obvious to most people here like "profile before optimize", "is this a symptom or the cause of the issue" are actually not that well understood in the large, unfortunately. All those are the symptoms of the same (lack of) skill for a programmer IMO.

aangjie2• 15 years ago

Hmm.....the place where i studied cognitive science, one common theme of most experiments were global vs local be it on visual perception/language/etc......Wondering is local being extolled too much nowadays..... reminds me of the other post on "How not to scale?"

apower2• 15 years ago

You are wrong, on both individual level and stereotyping to a nation of people.

On the individual level, he did do the debugging and analysis, on a smaller scope. Linus was asking a bigger scope analysis and a lot of work. Some people are willing to spend time to understand and fix problem for free. Some people have better things to do and aren't willing to spend the time to do it. That's their prerogative.

On a nation level, there are Chinese who want to get things done and there are Chinese who want to understand the root causes, just as there are people in other nations/cultures who want to get things done and there are people who want to understand the root causes.

gregschlom4• 15 years ago

Thanks for the explanation on the individual level. Sounds reasonable.

On your second point, yes, you can say of any cultural group that there are people who do X and people who do non-X, but that doesn't proves that there are no global traits and that all cultural stereotypes exists for no reason.

But I understand your point as "you are wrong to try to attribute the behavior of an individual to a stereotype, since they can only be used at a very broad level", and I think you're probably right.

muyuu• 15 years ago

It's not an acceptable approach in kernel development.

A patch like that has zero (actually, negative) value. It simply shouldn't be accepted and regressing to the last "working", most tested version should be the option.

So, all in all, if you are not willing to do your homework well enough, it's better for everybody if you don't bother at all. It wastes both your time and the maintainers' time. Linus' time no less.

nadam3• 15 years ago

"I don't know the Chinese culture well enough (assuming Yinghai is from China), but I am under the impression that they would emphasize more on results (fix the problem) than on processes (understand why the fix works, in order to be sure we are not breaking something else)."

The greatest living mathematician has Chinese origins: http://en.wikipedia.org/wiki/Terence_Tao

If someone 'thinks and analyzes problems' then he does.

I don't like categorization by nation because I am Hungarian and I am afraid a lot of people in the U.S. who don't know me yet thinks something entirely different of my problem solving style than reality.

gregschlom4• 15 years ago

Of course, any nation is able to produce any kind of individual.

I'm a great believer in cultural traits, and I think they are normal. We are not all identical, and we are not all totally randomly different. We all share some cultural background from the country we grew up in, in varying degrees, and it does not prevent any individual from having any specific ability.

Yet, I was wrong to try to correlate a specific behavior of a specific person to his/her culture. That's where my logic was flawed.

If anyone wants more insight on cultural differences, I really recommend "When Cultures Collide" from Richard Lewis, it's a great book.

khafra• 15 years ago

When I think of Hungarian problem solving I think of Polya's renowned book on proof heuristics, "How to Solve It"[1]. How accurate is that impression?

[1] http://www.math.utah.edu/~pa/math/polya.html

learner4life• 15 years ago

While Terrence was of Chinese origin, he certainly did not grow up imbued in the Chinese culture. He was more of an Australian. I not saying this to imply Chinese are not deep thinkers. I have worked with Chinese (China bred) engineers who are damn good thinkers. So it is just a matter of personal style and priority(influenced at times by the culture one grows in).

johngalt• 15 years ago

When I think "Hungarian problem solving" the first association that comes up is John Von Neumann.

What assumptions do you normally encounter?

misterbwong• 15 years ago

I've seen this behavior many times in 100% US dev teams. This happens because it tends to be the "easy" way out.

Hmm...there's a problem with this code. It looks like changing this index to start at 5 works. OK, bug fixed!

akent• 15 years ago

It gets better later in the thread:

Yinghai, we have had this discussion before, and dammit, you need to understand the difference between "understanding the problem" and "put in random values until it works on one machine".

"There was absolutely _zero_ analysis done. You do not actually understand WHY the numbers matter. You just look at two random numbers, and one works, the other does not. That's not "analyzing". That's just "random number games".

benwerd• 15 years ago

Well, there goes my development methodology.

ilitirit• 15 years ago

"Programming by coincidence"

http://pragprog.com/the-pragmatic-programmer/extracts/coinci...

lindvall2• 15 years ago

Another aspect of this thread that I find very refreshing is the fact that the previous implementation may have used magic numbers doesn't reduce anyones desire to actually understand what is going on going forward.

The realization that a magic number was already being used could have caused one of two outcomes:

a) justification for replacing one magic number with another

b) realization that more research needed to be done to understand exactly what was going on in the first place

I appreciate seeing (b) as the option chosen. We should all strive to be this diligent.

rams• 15 years ago

Programming by coincidence as the PragProg says (someone has already posted the link).It's extremely common here in most Indian companies, especially with freshers.

pjscott2• 15 years ago

Also known as shotgun debugging, where you randomly poke at the relevant portion of the source code in the hope that the bug will magically vanish. I think the habit is formed early on, when most of the mistakes are things like syntax errors or off-by-one problems, where certain types of random tweaking actually can be somewhat effective.

coderdude• 15 years ago

I always get a kick out of how Linus talks to people. It's so direct and he never coats his arguments to make them easier to swallow. You could learn a lot about not bullshitting from that guy.

muppetman2• 15 years ago

It's strange isn't it? When people do the same in places like this community (and other communities) they're immedietly downvoted or dismissed, unless they're someone held in similar esteem to Linus.

qq664• 15 years ago

It's not strange at all. Linus has earned his credibility. Some people in this community have too (pg, joshu, patio11, it's a long list). But people are downvoted when they act like they've earned credibility when they haven't.

kenver• 15 years ago

I guess people (especially smart ones) don't like being told they're wrong by anyone who they consider inferior even if that person is right. By inferior I mean anyone who can't immediately prove that they're superior by listing a bunch of amazing achievements.

reitzensteinm• 15 years ago

I think even here, where politeness is one of the stated goals of the community, people will forgive someone for being very direct (but not mean) if they're also insightful. My gut feeling says that if this conversation happened here and both parties were unknown people, Linus' posts would have gotten voted way up, because he's just so right.

But an attitude combined with less than excellent technical insight is, of course, going to get posts downvoted into oblivion. Well, -4, anyway.

bad_user• 15 years ago

http://en.wikipedia.org/wiki/Meritocracy

phillmv• 15 years ago

It's because being direct is not the same as being an immense prick.

Most people (including Linus at times, credibility does not make you immune) confuse that issue.

mynegation• 15 years ago

It is not strange at all. The purpose of kernel hackers is to build best OS possible and communication is a tool. If it has to be blunt and direct so be it.

HN on the other hand is the place where people come for communication and it is primary purpose, or secondary to - you know - news, but still very high on the list.

quanticle• 15 years ago

The difference with Linus, of course, is that he's so often correct. Its one thing to be a jerk. Its quite another to be a jerk that's right.

joe_the_user• 15 years ago

Actually,

When Zed Shaw says stuff here, I think sometimes it's up-voted and some times it's down-voted. Sometimes the up-voted stuff is good and sometimes times the down-voted stuff is bad.

In ways, I think that relationship is better. Zed has carved-out the position of being celebrity who's not automatically respected. Being a curmudgeon myself, I respect him more for this...

Also, I've seen some high karma folks here still get -4's (back when karm was visible).

cromulent• 15 years ago

It's something of a Finnish trait.

enjoy-your-stay• 15 years ago

Linus seems to be (correctly) railing against what is classic cargo cult behaviour.

Making changes until someting seems to "work".

smcl4• 15 years ago

I think Linus forgets that at one point he too was inexperienced and liable to make these hit-and-hope fixes. I agree with his point in general, but the dickish manner in which it's delivered isn't particularly helpful ("Why don't we write code that just works?")

qq664• 15 years ago

The thing is, if you're inexperienced and mistake-prone, work on a pet project to gain experience (like the Linux kernel in 1992, or your flavor of location-based mobile social coupon sharing app today). Don't start pushing magic numbers into a software product that millions of people depend on.

smcl4• 15 years ago

Yep, that'd be an excellent way to word it. As I said I don't disagree with the point, I just dislike how Linus addresses people sometimes.

alextingle3• 15 years ago

Why so sensitive? Seriously, when someone criticises your work, do you listen to what they say or do you just listen to their tone of voice?

If all you do is listen to the tone, then YOUR WORK WILL SUFFER. Because if someone comes up to you and says, "you dick! What the fuck were you thinking putting that double dereference there?? There's no way it could ever work!"

If you stop listening after, "you dick! What the fuck were you thinking..." then you will miss out on learning something that you should know. The person is angry BECAUSE you have been stupid. Yes, that sucks, and perhaps they should learn to control their temper. But you can't do that for them. What you CAN do is be less stupid next time!

smcl4• 15 years ago

I listen to what they say. I just lose respect for the person if they act like a bit of an idiot while delivering it. This is not helpful if the person is meant to be in a supervisory\managerial role.

to3m• 15 years ago

Well, I always listen to the tone of voice. This gives me a good indication of whether they're worth listening to or not.

Usually, people speaking with a scornful tone of voice (or the written equivalent) are more venting than they are providing useful information. There's no need to pay too much attention to whatever they have to say, because if it's a big deal they'll say it again once they've calmed down.

I've noticed that when programming computers there are very few problems that can be fixed by behaving like a dick. And those that can be fixed by behaving like a dick, can also be fixed whilst behaving in a more gentlemanly fashion. The rest can be left unsolved, politely. There's really no reason not to do this.

aangjie2• 15 years ago

Reminds me of some of my last work experiences...

ciupicri• 15 years ago

That patch reminds me about a nouveau bug[1] I had a couple of weeks ago. According to one of the developers behind nouveau it was caused by a new memory mapping/allocation scheme that broke things on systems with more than 4 GBs of RAM. Some device memory (registers etc) was mapped above 4 GBs and some of them don't like this. So he built a new kernel which reverted the change and the problem was "miraculously" fixed.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=689825

mv1• 15 years ago

I call this "poke it with a stick" debugging. Let's poke the code like this and see if it works now. This approach is so wrong yet so common it's infuriating.

j_baker• 15 years ago

I can't help being reminded of this hacker koan:

A novice was trying to fix a broken Lisp machine by turning the power off and on.

Knight, seeing what the student was doing, spoke sternly: "You cannot fix a machine by just power-cycling it with no understanding of what is going wrong."

Knight turned the machine off and on. The machine worked.

eof• 15 years ago

This, in turn, reminds me of a long-shot theory about how the universe works that I sometimes ponder.

I can't think of how many times someone has come to me with a computer problem, or I've gone to a vendor/support chat with a problem that hasn't worked dozens or hundreds of times. Then suddenly, with the guru there, whether it is me or someone else, suddenly the problem evaporates.

I've found myself wondering if this wasn't some illusion, but an actual artifact of the nature of the universe. Think about it: if noob's problems everywhere were actually the universe not letting their shit work, there would be no one to ever notice it; because when the expert comes in and fixes it, it is magic to the noob anyway, and the expert is 100% used to mundanes not having their stuff work for any given reason.

arethuza• 15 years ago

Sounds like quantum bogodynamics: http://www.catb.org/jargon/html/Q/quantum-bogodynamics.html

cakeface• 15 years ago

I like to call this the Scooby Doo effect. The ghost always appears for Scooby but not for the rest of the gang.

trafficlight• 15 years ago

We call it The Aura. Some people have it and some don't.

noonespecial• 15 years ago

We call it "personal entropy". Some people have more of it than others.

dasil003• 15 years ago

What about the case of a person who, when they show up, magically breaks all technology. I had a friend like that, "I didn't touch it I swear!"

freshhawk• 15 years ago

There is already a scientific explanation for this.

It's called "confirmation bias"

rokhayakebe• 15 years ago

If your Iphone starts blinking or vibrating randomly or does something weird repeatedly, do you take 10 minutes to understand what is happening or do you just turn it off/on?

woodrow• 15 years ago

And this reminds me of the "More Magic" switch on a PDP-10 at the MIT AI lab: http://www.catb.org/jargon/html/magic-story.html

dolinsky2• 15 years ago

At the risk of causing a bunch of you to spend the rest of the day watching the whole 3 seasons of The IT Crowd....The canonical answer to 'Have you tried turning if off and on again': http://www.youtube.com/watch?v=nn2FB1P_Mn8

jrockway• 15 years ago

There are 4 seasons, although I agree that season 2 is worth skipping.

pjscott2• 15 years ago

Important to understanding the joke is the fact that Tom Knight designed the processor for the Lisp Machine, and therefore his power-cycling is imbued with understanding.

kemiller• 15 years ago

I was all set to defend the "jiggle randomly" school of development with something along the lines of "sounds like someone who has never had an external deadline to worry about" but then I got really sad, and didn't.

"... so now I will jiggle things randomly until they unbreak" is not acceptable'

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