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Type in the exact number of machines to proceed

rachelbythebay.com

211–220 of 340 posts

Re: Type in the exact number of machines to proceed

#211
post #185

Github has been doing this for quite a while know when you try to delete a repository - you have to type in the exact repository name to confirm.

Which I always mindlessly copy and paste...

If you really think that’s an issue, pasting could be disabled for that input field. Would that make you happier?

It hasn’t been an issue for me, since repo names aren’t usually super long and onerous to type.

Re: Type in the exact number of machines to proceed

#212
post #125

I've seen this called "pointing and calling" [1], Japan's train drivers use the technique to force themselves to perform actions and take notice of the current environment. I personally took it to heart, it's a good system for forcing a cache miss in the brain - make sure you're on "database production" or "database localhost" etc. [1] https://en.wikipedia.org/wiki/Pointing_and_calling

This is true for NYC subways too! https://www.youtube.com/watch?v=i9jIsxQNz0M

The video doesn't really explain why conductors point at the signs - it just says "to prove they're paying attention". Paying attention to what? The answer is that they are verifying that the train is correctly positioned in the station so that all of the doors will open on the platform.

Explained here: https://www.nydailynews.com/new-york/mta-conductors-point-st...

Re: Type in the exact number of machines to proceed

#213

Earlier quoted context omitted.

I've only been in the job field for six years, and yet: My first boss accidentally deleted our QA database, meaning to delete a local copy A later boss accidentally deleted our production database, thinking it was the clone that he had just made (which luckily we still had) Both of them were very experienced developers in their 40s. Nobody is beyond this kind of mistake.

War story time. Long ago, I worked for an interesting company that insisted on running its entire business on Linux desktops, all the way back between 1999-2002. Imagine running StarOffice/OpenOffice, Thunderbird, Netscape Navigator, etc, for your entire business back in 2000, including your executive team, marketing teams, everyone, most of whom had never even heard of Linux before. Anyway, this being Linux, everyon…

That's a very sad worry story, hope it turned out OK. Sorry you and the users had to go through that.

Re: Type in the exact number of machines to proceed

#214
So, related obviously correct designs:

1. Git's Force-with-lease. Git push's "force" is too powerful, you will likely regret this much power, but it's tempting. So force-with-lease is the same power but conditional on you telling git what exactly the state was that you're overriding.

This has two benefits, one is like Rachel's, it is an opportunity for a human to stop for a moment and consider, wait, why are we overriding this state? To find out what it is we might as well read... oh the state says it's an "emergency fix. Call Jerry". Maybe, just maybe, I ought to call Jerry before I force overwrite it?

But the other is about race conditions which Rachel doesn't specifically address. If you are very careful to check that the state you want to overwrite with force is indeed a state that should be overridden, nothing prevents it meanwhile changing and then you overwrote state you didn't even know existed. But force-with-lease fixes that because your lease won't match.

I believe Force-with-lease is a pattern that ought to be far more widespread. I've used several configuration management tools that let somebody say "Temporarily don't mess with config on these machines" and some of them let you write a reason like "James is rebuilding the RAID arrays" but none of them have that force-with-lease pattern that would be let me say "I know James is rebuilding the RAID arrays, this change must happen anyway but if anything else is blocking the change then reject it and let me know".

2. Prefer Undo to Confirmation. If the computer can undo the action, even if that's a bunch of work and you'd rather not bother, put that work in and enable undo. Humans always know they "really" wanted to do the thing you're asking them to confirm so it's somewhat futile to ask, but they often realise they didn't want to afterwards and will undo it if you make that possible.

Not everything can be undone. Undo factory reset isn't a thing. But lots of things you can't undo it was just laziness, try to do better in your own software. Your users (which might include you) will be grateful.

Re: Type in the exact number of machines to proceed

#215
post #201

Earlier quoted context omitted.

Bash tip I picked up from observation - always start a potential command with # # rm -rf some_dir Then if you accidentally press return before completing it hasn't happened. When you have reviewed and are sure it is correct, you recall and delete the hash to execute - simples!

Does this work with autocomplete?

Just tried it with bash on Linux, and apparently autocomplete works in a comment.

Re: Type in the exact number of machines to proceed

#216

I've seen this called "pointing and calling" [1], Japan's train drivers use the technique to force themselves to perform actions and take notice of the current environment. I personally took it to heart, it's a good system for forcing a cache miss in the brain - make sure you're on "database production" or "database localhost" etc. [1] https://en.wikipedia.org/wiki/Pointing_and_calling

I've only been in the job field for six years, and yet: My first boss accidentally deleted our QA database, meaning to delete a local copy A later boss accidentally deleted our production database, thinking it was the clone that he had just made (which luckily we still had) Both of them were very experienced developers in their 40s. Nobody is beyond this kind of mistake.

Ironically there seems to be no time more prone to these kinds of mistakes than when you're trying to prevent or fix them.

Re: Type in the exact number of machines to proceed

#217
post #125

Earlier quoted context omitted.

This is true for NYC subways too! https://www.youtube.com/watch?v=i9jIsxQNz0M

The video doesn't really explain why conductors point at the signs - it just says "to prove they're paying attention". Paying attention to what? The answer is that they are verifying that the train is correctly positioned in the station so that all of the doors will open on the platform. Explained here: https://www.nydailynews.com/new-york/mta-conductors-point-st...

This comes up every few weeks on HN but nobody has ever offered any statistics that would suggest this is as good let alone better than just having the trains handle alignment automatically. It's a task humans are bad at and machines are good at, so just giving it to machines makes more sense, modulo unions.

London Underground hasn't had guards for decades at this point, and the Docklands Light Railway hasn't even had drivers (there is a member of staff who is trained to be able to drive it on every train, but they are usually doing other things) since its creation. If they're misaligning often enough for it to be possible for New York to be statistically better I haven't seen anything about it after repeatedly asking.

Re: Type in the exact number of machines to proceed

#218

Earlier quoted context omitted.

It isn't about testing if the president can do surgery. It is about forcing the president to look somebody in the eye before they kill them.

> It is about forcing the president to look somebody in the eye before they kill them. Right, but can you understand that 'the President being able to look somebody in the eye before they killing them' is not a requisite for 'the employment of nuclear weapons being justified'? We require the president to be able to do B before they can do A. But what if A is the right thing to do but the President is not able to do B…

I think that is the exact point though. The point of the interlock to force this logical dependency when there may not have been one before.

Re: Type in the exact number of machines to proceed

#219

Earlier quoted context omitted.

Which I always mindlessly copy and paste...

If you really think that’s an issue, pasting could be disabled for that input field. Would that make you happier? It hasn’t been an issue for me, since repo names aren’t usually super long and onerous to type.

> If you really think that’s an issue, pasting could be disabled for that input field. Would that make you happier?

many (most?) HN users probably have that disabled, because too many sites abuse it to block password managers, for "security reasons" .

Re: Type in the exact number of machines to proceed

#220

Earlier quoted context omitted.

>You can know that something is the right thing to do but not have the courage to physically harm someone to do it. In this specific case the "thing to do" is literally to harm hundreds of thousands of people. The reasoning behind this proposed interlock is that any logic which concludes that it is moral and rational to harm hundreds of thousands of people must also conclude that it is moral and rational to harm the…

> The reasoning behind this proposed interlock is that any logic which concludes that it is moral and rational to harm hundreds of thousands of people must also conclude that it is moral and rational to harm the "interlock" individual. Yes, but you can know it's the right thing to do, but not be able to physically do it. The president's ability to physically cut someone open is not relevant to whether it's a good ide…

> The president's ability to physically cut someone open is not relevant to whether it's a good idea to use nuclear weapons or not. Him being unable to do it tells you nothing about whether they should be launching the weapons.

Our emotional systems are the product of millions of years of evolution and often (not always, but often) show better judgement than our "higher" faculties. Bringing that part of our capabilities into the decision-making loop is a very good idea.

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