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Ask HN: What have you built with Erlang?

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Re: Ask HN: What have you built with Erlang?

#41

Post by uwiger »

rvirding wrote: post #37
acqq wrote: post #32

Earlier quoted context omitted.

AFAIK it was written as the research, not to run at any specialized hardware, then "sold" as being able to run the phone switch, but it needed a "big iron" computer attached to it just to drive that switch (!) -- it was that slow. And AFAIK it's still very slow. Up to quite recently it wasn't even able to use more cores.

Where did you get all that from? Erlang was never intended for research but as a tool for writing real switch applications. Yes, the original Prolog interpreter was slow, but that has not been used for almost 20 yrs. We never had "big iron" computers to play with, and never really needed them either as the system has been efficient enough to run on computers that were cost effective for the actual applications. The i…

Ericsson could have had a need for multicore already back in 1997, when the first SMP Erlang prototype was written, but the space and power budgets for the processor boards made it impossible to get any matching hardware for it. SMP in those days was not multicore, but several CPUs. It was only usable in servers - not in embedded systems.

Re: Ask HN: What have you built with Erlang?

#42

Post by acqq »

rvirding wrote: post #37
acqq wrote: post #32

Earlier quoted context omitted.

AFAIK it was written as the research, not to run at any specialized hardware, then "sold" as being able to run the phone switch, but it needed a "big iron" computer attached to it just to drive that switch (!) -- it was that slow. And AFAIK it's still very slow. Up to quite recently it wasn't even able to use more cores.

Where did you get all that from? Erlang was never intended for research but as a tool for writing real switch applications. Yes, the original Prolog interpreter was slow, but that has not been used for almost 20 yrs. We never had "big iron" computers to play with, and never really needed them either as the system has been efficient enough to run on computers that were cost effective for the actual applications. The i…

I remember reading "Erlang - A survey of the language and its industrial applications" (Joe Armstrong - in INAP'96)

Now I've checked again, so let me summarize:

It started to spread "outside the lab" in 1987. In 1995 there were three commercial applications: network simulator, mobility server and distributed resource controller. First is a simulator, not running on the specialized hardware, the third was running on "a network of Windows NT machines." The second: "acts as a call control system when linked to the PBX"

OK, the second was running on the additional SPARC-based machine, not big iron, but AFAIK certainly more powerful than the PC's of that time.

So I don't see anything that was targeting really "specialized hardware" particularly not what we'd think as embedded (less power consumption, slower processors than the PC CPU's). It was a research project, and it had traditionally performance problems.

Even today, after so many years, when you compare Erlang HiPe (Hi Perf, you can imagine others then!) with something higher than C, let's then say Lua JIT it's easy to see which one is faster:

http://shootout.alioth.debian.org/u32/benchmark.php?test=all...

Edit: Or for multi core 64 bits with Mono:

http://shootout.alioth.debian.org/u64q/benchmark.php?test=al...

Re: Ask HN: What have you built with Erlang?

#44

Post by evgen »

acqq wrote: post #42
rvirding wrote: post #37

Earlier quoted context omitted.

Where did you get all that from? Erlang was never intended for research but as a tool for writing real switch applications. Yes, the original Prolog interpreter was slow, but that has not been used for almost 20 yrs. We never had "big iron" computers to play with, and never really needed them either as the system has been efficient enough to run on computers that were cost effective for the actual applications. The i…

I remember reading "Erlang - A survey of the language and its industrial applications" (Joe Armstrong - in INAP'96) Now I've checked again, so let me summarize: It started to spread "outside the lab" in 1987. In 1995 there were three commercial applications: network simulator, mobility server and distributed resource controller. First is a simulator, not running on the specialized hardware, the third was running on "…

Do you realize that rvirding is Robert Virding, one of the creators of Erlang?

Re: Ask HN: What have you built with Erlang?

#45

Post by [deleted] »

evgen wrote: post #44
acqq wrote: post #42

Earlier quoted context omitted.

I remember reading "Erlang - A survey of the language and its industrial applications" (Joe Armstrong - in INAP'96) Now I've checked again, so let me summarize: It started to spread "outside the lab" in 1987. In 1995 there were three commercial applications: network simulator, mobility server and distributed resource controller. First is a simulator, not running on the specialized hardware, the third was running on "…

Do you realize that rvirding is Robert Virding, one of the creators of Erlang?

[deleted]

Re: Ask HN: What have you built with Erlang?

#46

Post by acqq »

evgen wrote: post #44
acqq wrote: post #42

Earlier quoted context omitted.

I remember reading "Erlang - A survey of the language and its industrial applications" (Joe Armstrong - in INAP'96) Now I've checked again, so let me summarize: It started to spread "outside the lab" in 1987. In 1995 there were three commercial applications: network simulator, mobility server and distributed resource controller. First is a simulator, not running on the specialized hardware, the third was running on "…

Do you realize that rvirding is Robert Virding, one of the creators of Erlang?

I referred to the work of Joe Armstrong (http://en.wikipedia.org/wiki/Joe_Armstrong_(programming)) written 15 years ago.

Is there something that's written there that's not true? I'd really like if Robert Virding can tell us some insider's stories. I remember also reading Armstrong's 1990 paper "Erlang - An Experimental Telephony Programming Language" where it's written "Erlang is a programming language designed for prototyping concurrent real-time distributed applications." That fits with the "simulator" application from the later paper and also fits to the "research" concept of the language.

I'd be also glad to hear where Erlang beats other languages in run-time performance (not in the aspect of "it's nicer to write in it"). I'd thank Robert Virding or anybody else for that.

Re: Ask HN: What have you built with Erlang?

#47

Post by lzw »

bosky101 wrote: post #26

- a key-value stored modeled caching system that can run functions during set/get, have expiry, counters, counters that wait for N as a buffer before running transactions, and machine learning - all as primitives. the tail-recursive processes acting as mini-servers holding state and the best thing is that you have a mini-automatic scaling if you combine this well with expiring of processes. increase load when there's…

Let me guess, all this over engineering nonsense set your startup back 3 years.

Re: Ask HN: What have you built with Erlang?

#48

Post by gleber »

Erlang is perfect for any messaging systems. And on other hand Erlang works well for GIS:

Vector Map Server - a BSc thesis project. Vector geospatial data streaming server, very similar thing to server's streaming vector data to Google Earth or Map24. Also works as WFS server. Has to handle a lot of data, but since data is mostly immutable it works well.

Backend service for not yet released liveblogging site. Done in collaboration with few other developers. Massive pubsub system. Done tests with 1M concurrent users on 200 small-node EC2 cluster with end-to-end latency mostly Texspace - spatial search server based on Microsoft Research paper. Fuzzy spatial search capable of working with completely unstructured queries. Had pretty big issues with processing, indexing and analyzing big amounts of data due to slowness of all DB solutions available at that time. Writing geometry algorithms in Erlang is not trivial due to immutability, since all of them are described in imperative languages.

IM subsystem for microblogging site (which is pretty big in Asia) - implemented 5 proprietary protocols. Erlang is perfect for such tasks! The only issue was lack of documentation for proprietary protocols ;)

Map routing server - implemented optimized A* search with route graph generalization. Writing fast A* is tricky in immutable world. Books like Okasaki's "Pure Functional Data Structures" FTW!

WMS Tiling / TMS service with caching. Simple and easy task for Erlang. Mnesia + file-level cache.

Overseer - Nitrogen + CouchDB app for tracking employees time by doing screenshots via VNC and marking them as "work" / "not work". A breeze :)

Erlang FTW!

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