It’s just data


Joe Armstrong: After a small amount of experimentation I was able to make Erlang talk to a web page using pure asynchronous message passing.  I think this means the death of the following technologies:

I see the appeal for a single node Erlang or Eventmachine or node.js server.  (Can sockets be passed between servers?)

I’m less clear about how this could work with request/response servers like PHP or Rails.  Event loops on the server are not typically application patterns for applications using such frameworks — shared nothing is more of the norm.

Regardless of how this pattern might work, it definitely seems a bit early to declare the death of that laundry list of popular web technologies.

Posted by Scott Johnson at

Sockets can be passed between servers, see; [link] for an example.

Posted by Colm MacCarthaigh at

Sockets can be passed between server

Forgive me, but unless I’m missing something, that only passes a socket between processes on a single server.

Posted by Sam Ruby at

No, You’re right - sockets can be moved between hosts, but it needs trickery like IPVS - [link] for an implementation.

Posted by Colm MacCarthaigh at

At this point I’m wondering if the Linux Virtual Server is a leaky abstraction or simply black magic.  Servers like node.js rely on the select API working fast, and I simply don’t see how that can be accomplished transparently and correctly across a network.

Posted by Sam Ruby at

All problems can be solved by adding another layer of abstraction, or in this case another tier. You could have a tier that manages the long-lived WebSocket connections and proxies events to a pool of app servers; I think Orbited already works this way.

Posted by Wes Felter at

It’s not that hard to share the state from a TCP stack across multiple hosts. In most implementations the incoming traffic is routed to a deterministic host (usually with flow hashing) in a cluster and then synchronized via a back-channel to the “moved to” target host. The target host then sends the outgoing traffic asymmetrically. The TCP state is synchronised (ala CARP) via the same shared channel. LVS is probably the most widely known, but there are other implementations of this technique, some load-balancers can do it too.

It can certainly be done across a network correctly, whether or not it’s efficient is a whole different question probably best put in terms of amdahl’s law.

Posted by Colm MacCarthaigh at

why only single node Erlang?

Posted by Robert Sayre at

My understanding, perhaps incorrect, is that a socket, once open, is bound to a specific host.  I don’t understand how another layer of abstraction or deterministic hosts allows one to effectively load balance, something which often needs to be done retroactively.

I’m entirely OK with WebSockets solving a common, albeit not universal problem — yielding to the current solutions to address the remaining needs.

Or perhaps this needs to be addressed at at the application level.

Posted by Sam Ruby at

I must be missing something, because this looks like the exact problem distributed Erlang was designed to solve. Wouldn’t the design to go with be a pretty simple socket reader process with the actual application workload executed in a different Erlang process that may or may not be on the same node?

I do agree that the last two bullet points probably won’t vanish because of web sockets.

Posted by Robert Sayre at

It wouldn’t be just a reader process: in order to send data back, one would have to find the server with the socket.  But you are right, this can be solved via application code in Erlang.  I’m still less clear on how this could work with PHP or Rails.

Posted by Sam Ruby at

Youre so cool! I dont suppose Ive learn anything like this before. So good to seek out any person with some unique ideas on this subject. realy thanks for starting this up. this website is something that’s needed on the net, someone with a bit of originality. useful job for bringing something new to the web!
wbresultsnic in 2018

Posted by wbresultsnic in 2018 at

I like this  site  very much so much good  information.

Posted by Airconditioning at

Currently it looks like BlogEngine is the best blogging platform available right now. (from what I’ve read) Is that what you’re using on your blog?
بهترین وکیل ملکی

Posted by بهترین وکیل ملکی at

depending on fossil fuel is always a bad idea, we should always concentrate on renewable energy.
fazer formula negocio online

Posted by fazer formula negocio online at

Visit our site for information about  securities based lending and more. There is information about stock and equity loans as well as application forms.
Lucht/lucht warmtepomp

Posted by Lucht/lucht warmtepomp at

auto insurance is indeed very important, insurance can protect your property.. Dental Implant Richardson

Posted by Dental Implant Richardson at

There’s no doubt that, a man or woman until they offer trust, or simply allow individuals trust.
Aanleggen zwembad

Posted by Aanleggen zwembad at

There are three eras of vintage watches, The Original Vintage Era, The Brand Years, and the New Designs Era. how does rent to own work

Posted by how does rent to own work at

You really should be a part of a contest for just one of the finest blogs on-line. I am going to recommend this great site! Juliano

Posted by Juliano at

Vielen dank für den Artikel. daraus kann man sich einen guten Eindruck verschaffen Grüsse Meike kiseonik

Posted by kiseonik at

i would love to get some free calendars on the internet, are there are sites or company that gives one?’ Mobile App Development Company in Dubai

Posted by Mobile App Development Company in Dubai at

Add your comment