You can definitely average two relatively accurate chronometers but you if you only have two it’s difficult to tell if one is way fast or way slow.
In a perfect world they drift less than a minute per day and you’re relatively close to the time with an average or just by picking one and knowing that you don’t have massive time skew.
I believe this saying was first made about compasses which also had mechanical failures. Having three lets you know which one failed. The same goes for mechanical watches, which can fail in inconsistent ways, slow one day and fast the next is problematic the same goes for a compass that is wildly off, how do you know which one of the two is off?
> In a perfect world they drift less than a minute per day...
A minute per day would be far too much drift for navigation, wouldn't it?
From Wikipedia [1]:
> For every four seconds that the time source is in error, the east–west position may be off by up to just over one nautical mile as the angular speed of Earth is latitude dependent.
That makes me think a minute might be your budget for an entire voyage? But I don't know much about navigation. And it is beside the point, your argument isn't changed if we put in a different constant, so I only mention out of interest.
> Having three lets you know which one failed.
I guess I hadn't considered when it stops for a minute and then continues ticking steadily, and you would want to discard the measurement from the faulty watch.
But if I just bring one watch as the expression councils, isn't that even worse? I don't even know it malfunctioned and if it failed entirely I don't have any reference for the time at the port.
My interpretation had been that you look back and forth between the watches unable to make a decision, which doesn't matter if you always split the difference, but I see your point.
> A minute per day would be far too much drift for navigation, wouldn't it?
Even that was much better than the dead-reckoning they had to do in bluewater before working chronometers were invented. Your ship's "position" would be a triangle that might have sides ten miles long at lower latitudes.
I’ve never heard the bring one or three, I’ve always just heard three. I think that exact saying implies that if you have two and one isn’t working out you’ll go crazy but if you have one you’ll be oblivious until it’s too late.
A well serviced rolex in 2026 with laser cut gears drifts +/- 15sec per day.
One with hand filed gears is going to be +/- a minute on a good day, and that’s what early navigation was using. I have watches with hand filed gears and they can be a bit rough.
Prior to that, it was dead reckoning, dragging a string every now and again to calculate speed and heading and the current and then guesstimating your location on a twice daily basis.
Those two wildly inaccurate systems mapped most of the world for us.
Reading the comment thread here made me realize the idea seems to be that having 2 just means double the probability of one of them failing in some undetectable way. The resulting error magnitude is reduced by half, but the probability of that error is doubled. So it gains you nothing to expected value to have 2. Unlike with 3, where the probability of undetectable failure and the error rate from partial failure are both reduced by the ability to make comparative measurements (eg pick the middle number not the average)
Though not without significant errors, the most amusing to me being that islands had a tendency to multiply because different maps would be combined and the cartographer would mistake the same island on two maps as being separate islands due to errors. A weird case of aliasing I suppose.
The book “Longitude” is fascinating, and discusses the challenges prior to chronometers (many people died), as well as the rewards offered for a precise chronometer, the attempts, etc.
I hope not because I’ve been doing my US taxes on Linux for 15 years.
It’s probably a specific windows desktop app, probably TurboTax by intuit, the company that lobbies to make filing your taxes hard and to destroy any free simple government app to file taxes.
So, not sure why they’d complain about not being able to help shoot their foot off but we all have preferences. :shrug:
My sister was the same, she brought her machine over, I booted a Ubuntu disk and did the disk config in the install and then she set the rest of the stuff up and I haven’t heard from her about it for 5 years, other than that I check if she’s still using it now and again.
If you do regulate. We currently have full regulatory capture in most industries and regulators that are doing their jobs are either hamstrung or the laws are so far behind the industries that they can’t or won’t work.
The key to proper regulation is to keep money and influence from pooling at the top, making it difficult for any single person to buy enough influence.
As it is, we have a dozen monopolies that should be broken up that are making a small section of the population so rich they are essentially above laws.
But, proper regulation can exist if people want it, and more specifically in the case of the USA, legislators want it. Unfortunately, Dems actively prevent it, and republicans are ripping it down, so the rest of us are kinda fucked.
Regulations can work if bypassing the regulation in question does not open up a market that is large enough to keep paying off the regulators.
For example, if there is only one regulator for a country, the companies can pay millions to get it eased up for them, because they can make billions from it.
But if there one regulator for each state, they equation will change and it might not be profitable to pay millions to a regulator of the state, because they cannot make enough profit from selling in the state to justify it.
That is the only way to make it work. Rules don't work forever. Incentives do.
Well, There's not going to be much because it would violate NDA, but, nothing is 'elastic'.
Somewhere, someone, has to buy a set amount of servers, based on a running capacity projection and build those into usable machines. The basis of a datacenter, is an inventory system, a dhcp server, a tftp server, and a DNS server that get used to manage the lifecycle of hardware servers. That's what everyone did at one point, and the best of them build themselves tooling.
What amazon has is built on what was available at the time both for tooling and existing systems that they'd have to integrate with. You almost certainly don't have to build anything that complex. Additionally, you can get an off the shelf DCIM that integrates with your DHCP and DNS servers and trigger ansible runners in your boot sequences that handle the lifecycle steps. It's considerably easier to do now than it was 15 years ago.
While they don't use AWS specifically for a lot of stuff, the internal tooling can still build thousands of boxes an hour though they don't really pay for UI work for that stuff.
You can put a host(s) in a fleet, tell it the various software sets you want installed and click go and you'll have a fleet when you come back, so don't think that what you're being asked to build is impossible or not being used under every single major cloud provider or VPS provider.
The slightly harder part is deciding what you're going to give to devs for a front end. Are you providing raw hosts, VMs, container fleets, all of it? how are you handling multi-zone or multi-region . . ., how are you billing or throttling resources between teams.
The beauty of this is you get a lot of stuff for free these days. You can build out a fleet, provide a few build scripts that can be pulled into some CI/CD pipeline in your code forge of choice and you don't really need to build a UI.
Provisioning tooling is hard, but it's a lot easier now that it was 15/20 years ago and all the parts are there. I've built it several times on very small teams. I would have loved to have 10 devs to build something like that, but the reality is that you can get 80% with a little glue code and a few open source servers.
Who’s using an experimental filesystem and risking critical data loss? Rule one of experimental file systems is have a copy on a not experimental file system.
The biggest dirty secret of the IT world is that everyone knows you should have more backups than God, but everyone runs with an average of about zero.
Sure, and when I go, 'I'm just going to slap this together and if it dies I'll rebuild it' I run on ext4 instead of an experimental service. If there is a reason that I need to run something 'experimental' you gonna bet your ass that I'm going to back things up.
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