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Reaching people on the internet

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Reaching people on the internet

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MacJL
25 days ago
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France
popular
25 days ago
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gglockner
25 days ago
You missed the best part: https://twitter.com/Oatmeal/status/923250055540219904
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4 public comments
vfxGer
25 days ago
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Glad I still use RSS
Gregidon
24 days ago
Indeed, no algorithm to decide what I want to see
BLueSS
25 days ago
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The Oatmeal is about 3 years behind the times on this one.
cygnoir
25 days ago
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I miss the old days.
Portland, OR, USA
expatpaul
26 days ago
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We brought it on ourselves
Belgium

Mac OS arrive sur Internet Archive

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The Internet Archive proposer d'utiliser d'anciens jeux et systèmes d'exploitation qui ont été portés en Javascript.

MacOS 6 et 7 viennent d'y faire leur apparition.

Si vous avez envie d'un peu de nostalgie ou seulement de voir combien les systèmes d'exploitation d'Apple ont progressé, allez-y faire un tour:
https://archive.org/details/softwarelibrary_mac

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MacJL
190 days ago
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France
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Insolite : de quelle couleur est cette robe "qui a cassé internet" ?

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Avant d'aller plus loin, répondez-donc à ce petit sondage :- "Dis Laura, tu la vois de quelle couleur, cette robe ?"- "Bah... Blanche et dorée, pourquoi ?"- "T'es sérieuse ? Parce qu'elle est bleue et noir..."- "Nannn tu déconnes ! Elle est dorée et blanche ! Attends, on appelle Aline..."- (Aline) "Elle est noire et bleue, pourquoi ?"On verra ce qu...
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MacJL
247 days ago
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France
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Stop Jupiter

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Stop Jupiter

I understand that the New Horizons craft used gravity assist from Jupiter to increase its speed on the way to Pluto. I also understand that by doing this, Jupiter slowed down very slightly. How many flyby runs would it take to stop Jupiter completely?

—Dillon

More than we can afford.

Spacecraft sometimes perform close flybys of heavy, fast-moving planets, which can let them gain speed without using fuel.[1]It may sound strange that you could gain speed by flying toward a planet and then away from it, since intuitively it seems like any speed you gain from flying toward it, you should lose flying away. But it's not really about gravity at all; gravity assists could work just as well with ropes or springs, if you could make them big enough. When you you fly toward a planet, swing around it, and fly back in the direction you came, it's as if you "bounced off" the planet. If the planet is moving, this bounce can give you an extra kick—like a tennis ball thrown at the windshield of a passing truck. You can check out What If #38 for details—or, at least, a drawing of the tennis ball thing. Due to conservation of momentum, the maneuver also slows the planet down very slightly, but no one really worries about that.

Planets don't slow down much during a flyby because they're so much heavier than spacecraft. When New Horizons flew by Jupiter, it gained about 4,000 m/s of velocity, while Jupiter lost about 10-21 m/s.[2]The geometry is a little complicated, since they were changing both speed and direction. If you want to learn more, look for a copy of this paper; it's a great tutorial.

10-21 meters per second may not sound like much, but it very slightly changed Jupiter's orbit, shortening its year and bringing it slightly closer to the Sun. Thanks to that flyby, by the time the Sun goes supernova, Jupiter's calendar will be several dozen nanoseconds out of sync from where it would be otherwise!

"Several dozen nanoseconds out of sync" isn't really satisfying, so we'll definitely need more than one flyby. How many can we pull off?

The New Horizons mission cost the US government about \$700,000,000 over the full planned lifetime of the mission from 2001 to 2016. Over that same period, the government spent about \$47,879,840,000,000 on other things. If we cut all the spending on those other things[3]It's probably nothing important. and funneled it all into New Horizons probes, we could have launched 68,000 identical New Horizons probes.

This would create some problems. For one, New Horizons carries a chunk of plutonium for power. This chunk—about 10 kg of it—was made from uranium in a reactor. To make enough plutonium for 68,000 New Horizons would require a substantial chunk of the world's uranium reserves.

But it gets worse.[4]It always seems to, with plutonium. When NASA launches a spacecraft carrying plutonium, they estimate the odds of a launch accident which would release radioactive material into the atmosphere. Usually, these odds are around 1 in 300. With 68,000 launches, then, we can expect a little over 200 nuclear accidents, which probably isn't good.

But it would all be worth it if we could slow down Jupiter! Sadly, 68,000 New Horizons probes aren't nearly enough. We'd still only rob Jupiter of a tiny fraction of its speed. Over the lifetime of the Solar System, the error in Jupiter's calendar would only add up to 2 milliseconds.

If we made the spacecraft cheaper, we could send more of them, but sooner or later we'd start running out of materials. We'd definitely run out of fuel for all these rocket launches, but let's assume we've built some kind of space elevator to make launches cheap. We'd run out of uranium (to make the plutonium) pretty quickly, but we could replace the uranium with a chunk of lead—after all, this spacecraft doesn't really need to work.

Eventually, though, we'd start running out of lead, too. If we replaced the lead with something else—say, rocks, or old garbage—we'd run out of that, too. At some point, in our desperate attempts to reduce Jupiter's forward speed, we'd be reduced to stuffing handfuls of rocks and dirt into a burlap sack with a NASA logo on the side.

Then, believe it or not, we would run out of rocks.

The Earth's crust only has so much stuff[5]This is the technical term. in it. Even if we peeled up the upper few dozen kilometers of crust and flung it at Jupiter—and for the record, I do not recommend we do this—it would trim less than a single mile per hour off Jupiter's speed.

Really, it makes sense that this plan doesn't work. Earth weighs a lot less than Jupiter,[6]Earth weighs almost exactly pi milliJupiters. so even if we throw the entire Earth at Jupiter, it would still only reduce Jupiter's speed by a fraction of a percent—on the order of a few dozen miles per hour. The situation is similar to the one in the tennis ball analogy from earlier: If you want to stop a truck with tennis balls, the tennis balls need more momentum than the truck, which means they need to be extremely heavy, fast, or both.

And at the core, that's the problem with this idea. Gravity assists are just like throwing a tennis ball at a speeding truck, and to stop a truck ...

... you need an awfully big tennis ball.

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MacJL
247 days ago
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France
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pmac
642 days ago
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lol. the tennis ball says "penn 15", or "pennis". It's a dick joke.
Atlanta, GA

Heroku is dead – no-one uses it anymore. You need to use Docker now

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rabbit_hole

Hey, my boss said to talk to you - I hear you know a lot about web apps?

-Yeah, I’m more of a distributed systems guy now. I’m just back from ContainerCamp and Gluecon and I’m going to Dockercon next week. Really excited about the way the industry is moving - making everything simpler and more reliable. It’s the future!

Cool. I’m just building a simple web app at the moment - a normal CRUD app using Rails, going to deploy to Heroku. Is that still the way to go?

-Oh no. That’s old school. Heroku is dead - no-one uses it anymore. You need to use Docker now. It’s the future.

Oh, OK. What’s that?

-Docker is this new way of doing containerization. It’s like LXC, but it’s also a packaging format, a distribution platform, and tools to make distributed systems really easy.

Containeri.. — what now? What’s LXE?

-It’s LXC. It’s like chroot on steroids!

What’s cher-oot?

-OK, look. Docker. Containerization. It’s the future. It’s like virtualization but faster and cheaper.

Oh, so like Vagrant.

-No, Vagrant is dead. Everything is going to be containerized now, it’s the future.

OK, so I don’t need to know anything about virtualization?

-No, you still need virtualization, because containers don’t provide a full security story just yet. So if you want to run anything in a multi-tenant environment, you need to make sure you can’t escape the sandbox.

OK, I’m getting a little lost here. Let’s back it up. So there’s a thing like virtualization, called containers. And I can use this on Heroku?

-Well, Heroku has some support for docker, but I told you: Heroku’s dead. You want to run your containers on CoreOS.

OK, what’s that?

-It’s this cool Host OS you can use with Docker. Hell, you don’t even need Docker, you can use rkt.

Rocket?

-No, rkt.

Right, Rocket.

-No, it’s called rkt now. Totally different. It’s an alternative containerization format that isn’t as bundled together as Docker is, and so it’s more composable.

Is that good?

-Of course it’s good. Composability is the future.

OK, how do you use it?

-I don’t know. I don’t think anyone uses it.

Sigh. You were saying something about CoreOS?

-Yeah, so it’s a Host OS you use with Docker.

What’s a Host OS?

-A Host OS runs all your containers.

Runs my containers?

-Yeah, you gotta have something run your containers. So you set up like an EC2 instance, you put CoreOS on it, then run the Docker daemon, and then you can deploy Docker images to it.

Which part of that is the container?

-All of it. Look, you take your app, write a Dockerfile, turn it into an image locally, then you can push that to any Docker host.

Ah, like Heroku?

-No, not Heroku. I told you. Heroku is dead. You run your own cloud now using Docker.

What?

-Yeah, it’s real easy. Look up #gifee.

Gify?

-“Google’s infrastructure for everyone else”. You take some off the shelf tools and stacks, using containers, and you can have the same infrastructure Google has.

Why don’t I just use Google’s thing?

-You think that’s going to be around in 6 months?

OK, doesn’t someone else do hosting of this stuff? I really don’t want to host my own stuff.

-Well, Amazon has ECS, but you gotta write XML or some shit.

What about something on OpenStack?

-Ew.

Ew?

-Ew.

Look I really don’t want to host my own stuff.

-No, it’s really easy. You just set up a Kubernetes cluster.

I need a cluster?

-Kubernetes cluster. It’ll manage the deployments of all your services.

I only have one service.

-What do you mean? You have an app right, so you gotta have at least 8-12 services?

What? No, just one app. Service, whatever. Just one of them.

-No, look into microservices. It’s the future. It’s how we do everything now. You take your monolithic app and you split it into like 12 services. One for each job you do.

That seems excessive.

-It’s the only way to make sure it’s reliable. So if your authentication service goes down…

Authentication service? I was just going to use this gem I’ve used a few times before.

-Great. Use the gem. Put it into it’s own project. Put a RESTful API on it. Then your other services use that API, and gracefully handle failure and stuff. Put it in a container and continuously deliver that shit.

OK, so now that I’ve got dozens of unmanageable services, now what?

-Yeah, I was saying about Kubernetes. That let’s you orchestrate all your services.

Orchestrate them?

-Yeah, so you’ve got these services and they have to be reliable so you need multiple copies of them. So Kubernetes makes sure that you have enough of them, and that they’re distributed across multiple hosts in your fleet, so it’s always available.

I need a fleet now?

-Yeah, for reliability. But Kubernetes manages it for you. And you know Kubernetes works cause Google built it and it runs on etcd.

What’s etcd?

-It’s an implementation of RAFT.

OK, so what’s Raft?

-It’s like Paxos.

Christ, how deep down this fucking rabbit hole are we going? I just want to launch an app. Sigh. Fuck, OK, deep breaths. Jesus. OK, what’s Paxos?

-Paxos is like this really old distributed consensus protocol from the 70s that no-one understands or uses.

Great, thanks for telling me about it then. And Raft is what?

-Since no-one understands Paxos, this guy Diego…

Oh, you know him?

-No, he works at CoreOS. Anyway, Diego built Raft for his PhD thesis cause Paxos was too hard. Wicked smart dude. And then he wrote etcd as an implementation, and Aphyr said it wasn’t shit.

What’s Aphyr?

-Aphyr is that guy who wrote, ‘Call Me Maybe.’ You know, the distributed systems and BDSM guy?

What? Did you say BDSM?

-Yeah, BDSM. It’s San Francisco. Everyone’s into distributed systems and BDSM.

Uh, OK. And he wrote that Katy Perry song?

-No, he wrote a set of blog posts about how every database fails CAP.

What’s CAP?

-The CAP theorem. It says that you can only have 2 out of 3 of Consistency, Availability and Partition tolerance.

OK, and all DBs fail CAP? What does that even mean?

-It means they’re shit. Like Mongo.

I thought Mongo was web scale?

-No one else did.

OK, so etcd?

-Yeah, etcd is a distributed key-value store.

Oh, like Redis.

-No, nothing like Redis. etcd is distributed. Redis loses half its writes if the network partitions.

OK, so it’s a distributed key-value store. Why is this useful?

-Kubernetes sets up a standard 5-node cluster using etcd as a message bus. It combines with a few of Kubernetes’ own services to provide a pretty resilient orchestration system.

5 nodes? I have one app. How many machines am I gonna need with all this?

-Well, you’re going to have about 12 services, and of course you need a few redundant copies of each, a few load balancers, the etcd cluster, your database, and the kubernetes cluster. So that’s like maybe 50 running containers.

WTF!

-No big deal! Containers are really efficient, so you should be able to distribute these across like 8 machines! Isn’t that amazing?

That’s one way to put it. And with all this, I’ll be able to simply deploy my app?

-Sure. I mean, storage is still an open question with Docker and Kubernetes, and networking will take a bit of work, but you’re basically there!

I see. OK, I think I’m getting it.

-Great!

Thanks for explaining it.

-No problem.

Let me just repeat it back to see if I’ve got it right.

-Sure!

So I just need to split my simple CRUD app into 12 microservices, each with their own APIs which call each others’ APIs but handle failure resiliently, put them into Docker containers, launch a fleet of 8 machines which are Docker hosts running CoreOS, “orchestrate” them using a small Kubernetes cluster running etcd, figure out the “open questions” of networking and storage, and then I continuously deliver multiple redundant copies of each microservice to my fleet. Is that it?

-Yes! Isn’t it glorious?

I’m going back to Heroku.

Want to use Docker and Continuously Deliver that shit? Check out CircleCI’s Docker Support.

Our followup.


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MacJL
247 days ago
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France
popular
458 days ago
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brico
458 days ago
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I lol'd
Brooklyn, NY
peelman
458 days ago
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Everytime I look into Docker, this is where I end up.

I did containers in 2009 with Softgrid and App-V before it was cool and when it was still a collection of Windows hacks.

Now we have Docker, a collection of Linux hacks, with a lot of the fundamentals in place but none of the finish that make it solution ready.
Seymour, Indiana
subbes
459 days ago
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"Yeah, BDSM. It’s San Francisco. Everyone’s into distributed systems and BDSM."
SF Bay Area
awilchak
460 days ago
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I wish I had written this
Brooklyn, New York
fxer
460 days ago
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Best docker dialogue since Hitler.
Bend, Oregon

Les instituts de sondage revoient leurs modèles de projection

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Vous pouvez me suivre sur twitter , sur facebook et sur google

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MacJL
364 days ago
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France
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