3 ms·

In fact, there is no such thing as an immutable or stateless computer; it violates the theory of computing. Just a bunch of buzzword nonsense people say so that

In fact, there is no such thing as an immutable or stateless computer; it violates the theory of computing. Just a bunch of buzzword nonsense people say so that they can justify spending their entire life asking for too much money to try making the machine behave as though it is stateless. With real, physical machines; you could have a cooling issue (which you should fix), a manufacturing defect (which you should RMA), a networking issue (which you should fix). All of these can easily be unique to an instance, and all of them need analytical attention; especially when you're paying for all of those machines "horizontally" and "at scale".

amalcon 10y ago
I mean, you can have an immutable stateless computer, but it's just called a "boolean logic circuit". You give it an input, it gives you an output, that's all. In practice, you'll of course actually be using a computer with RAM. Most likely, it will even have a Von Neumann architecture. That leaves you open to everything from race conditions to hardware failures to cosmic rays putting a machine into a bad state.
- deleted 10y ago
  [deleted]
drdrey 10y ago
Stateless depends on the context, it doesn't violate any theory of computing. Here are some elements of stateless systems: * all the state needed for serving requests is transient, not something that needs to be persisted * any particular instance can disappear without affecting the observable behavior of the system * the system is infinitely scalable: it doesn't matter if the cluster is comprised of 1, 100 or 1000 instances
BraveNewCurency 10y ago
> In fact, there is no such thing as an immutable or stateless computer Nobody calls the computer immutable/stateless. Immutable/stateless is an architecture pattern, implying that nothing important is stored or shared between calls. It doesn't say that you can't cache info or write log files, etc. > Just a bunch of buzzword nonsense Well, what's the alternative that you propose? Should my HTTP requests leave lots of state-full files laying around? Is it easier to manage deployments when every box has different files laying around depending on how old it is? Also, remember these techniques are for people "at scale". If you only have 1 or 2 boxes, these techniques may not be useful to you, so feel free to ignore them. I've got a 1000 boxes, and have seen first hand why it's a bad idea for each box to be able to be a unique snowflake. Even if you have physical machines, you shouldn't put your production image on it to debug it -- you should put a debug image on it that allows SSH. If it's a hardware problem, it will be easy to find. If it's a software problem -- well, you have 1000 other boxes running that software, so you'll see it again. Just add better logging.

amalcon 10y ago

I mean, you can have an immutable stateless computer, but it's just called a "boolean logic circuit". You give it an input, it gives you an output, that's all. In practice, you'll of course actually be using a computer with RAM. Most likely, it will even have a Von Neumann architecture. That leaves you open to everything from race conditions to hardware failures to cosmic rays putting a machine into a bad state.

deleted 10y ago
[deleted]

drdrey 10y ago

Stateless depends on the context, it doesn't violate any theory of computing. Here are some elements of stateless systems: * all the state needed for serving requests is transient, not something that needs to be persisted * any particular instance can disappear without affecting the observable behavior of the system * the system is infinitely scalable: it doesn't matter if the cluster is comprised of 1, 100 or 1000 instances

BraveNewCurency 10y ago

> In fact, there is no such thing as an immutable or stateless computer Nobody calls the computer immutable/stateless. Immutable/stateless is an architecture pattern, implying that nothing important is stored or shared between calls. It doesn't say that you can't cache info or write log files, etc. > Just a bunch of buzzword nonsense Well, what's the alternative that you propose? Should my HTTP requests leave lots of state-full files laying around? Is it easier to manage deployments when every box has different files laying around depending on how old it is? Also, remember these techniques are for people "at scale". If you only have 1 or 2 boxes, these techniques may not be useful to you, so feel free to ignore them. I've got a 1000 boxes, and have seen first hand why it's a bad idea for each box to be able to be a unique snowflake. Even if you have physical machines, you shouldn't put your production image on it to debug it -- you should put a debug image on it that allows SSH. If it's a hardware problem, it will be easy to find. If it's a software problem -- well, you have 1000 other boxes running that software, so you'll see it again. Just add better logging.