Comments on: The Scala vs Erlang whirlwind

By: Janko in a Jar » Blog Archive » Mochiads injection

Janko in a Jar » Blog Archive » Mochiads injection — Mon, 19 Oct 2009 06:10:31 +0000

[...] The Scala vs Erlang whirlwind [...]

By: Ulf Wiger

Ulf Wiger — Sun, 25 May 2008 21:33:12 +0000

@jherber The great language shootout obviously should be taken with a huge grain of salt, but I thought I’d just mention that the thread-ring benchmark specifies exactly 503 processes, which is hardly enough to reason about differences when running hundreds of thousand processes.

It’s noteworthy, perhaps, that among the top entries in that benchmark, Erlang, Mozart, SML and Scala use a message-passing solution, while Haskell, Smalltalk, GCC and Lisaac all rely on a mutable shared token.

Personally, I think it’s interesting and fun that both Scala and Erlang are gaining ground. Perhaps trying to master both is a worthwhile pursuit?

By: MickaÃ«l RÃ©mond

MickaÃ«l RÃ©mond — Sun, 25 May 2008 15:06:41 +0000

We have tried the SNMP module as it is one of the basic feature for our supervision console for ejabberd. It works well. If you know what you do you can gather very low level information about Erlang, the state of the VM, etc.

By: Jim Roepcke

Jim Roepcke — Fri, 23 May 2008 19:03:09 +0000

jherber: I haven’t published my results yet, I’m refining my paper, I might submit it to the ICFP Erlang workshop.

By: orcmid

orcmid — Fri, 23 May 2008 15:45:37 +0000

Wow! You do “see spot run” very well. Nice. I don’t have any stake in this particular debate, but it is nice to have an appraisal like yours to get a feel for the concerns and approaches.

By: jherber

jherber — Fri, 23 May 2008 14:57:58 +0000

@Jim Roepcke do you have a blog write up of what you were specifically benchmarking between actor frameworks? the great language shootout clearly shows that for creating N actors and passing messages between them, erlang > scala, but not by “orders of magnitude”. i’ve also heard d.pollack make a case that for actual processing (what you do with the message) that scala is many times faster than erlang.

By: Ted Leung

Ted Leung — Fri, 23 May 2008 14:29:43 +0000

Rich,

I agree that Click/Goetz are heavily invested in the existing Java infrastructure, and I am not sure that I agree with their assertion that the OS and VMs are ready to go. But I don’t think that any of the potential models have proven themselves on a very broad scale.

I think that they danced around your point on mutable stateful objects, and I also suspect that mutable objects represent problems for concurrency.

By: Nolan Eakins

Nolan Eakins — Fri, 23 May 2008 12:43:39 +0000

I think we do have a model for concurrent programming: actors/processes that send and receive messages. I personally can’t imagine another model, well maybe actors/processes that share memory!

By: Rich Hickey

Rich Hickey — Fri, 23 May 2008 11:53:05 +0000

I attended that Click/Goetz talk and was disappointed. Clearly both speakers are heavily invested in the status quo. There are plenty of potential models, actors/message-passing, tuplespaces and transactions among them, and they are pretty old. Click/Goetz were right – they/Java don’t have a model. But while they kicked sand at Erlang and STM, they failed to acknowledge the elephant in the room – it’s quite likely that the traditional OO architecture of a program as a graph of mutable stateful objects, exemplified by Java/C#/Python/Ruby et al, is a poor fit for concurrency.

By: vincent

vincent — Fri, 23 May 2008 11:33:47 +0000

I know you were citing Ted, but the statement about Erlang’s missing SNMP functionality is false.

I haven’t used myself, so I can’t comment on its quality, but Erlang’s SNMP support seems pretty decent:

http://www.erlang.org/doc/apps/snmp/part_frame.html

By: Jim Roepcke

Jim Roepcke — Fri, 23 May 2008 09:00:17 +0000

Erlang already has built-in SNMP support. It might not be at the BEAM/VM level (I haven’t tried it yet), but adding Erlang-style processes to the JVM or CLR would be *at least* as hard, probably much harder, considering the shared-memory semantics of most languages not named Erlang.

I researched the Actor model this year, and wrote the same program in Erlang, Scala, Rubinius and Io using their Actor/Erlang-style concurrency libraries. Erlang was orders of magnitude faster than the other three, and Scala was the slowest. Also, I was able to run hundreds of thousands of Erlang processes on my MBP, whereas I couldn’t get even a few hundred running reliably in Scala or Rubinius. Io scaled to thousands of coroutines in my testing, but not tens or hundreds of thousands.

References:
http://erlang.org/doc/apps/snmp/index.html
http://www.erlang.org/doc/pdf/snmp.pdf