how to scale into the cloud using process? example computing simple average

[Steve Davis]

I too got triggered off by the mention of that word "cloud".

Note that each process that you spawn never sends a message back with
the result!

Have a good read about spawning processes and particularly about inter-
process messaging with send and receive in Joe's book. You can get the
PDF immediately from...

http://www.pragprog.com/titles/jaerlang/programming-erlang

regs,
/s



On May 30, 12:42 pm, Kid Erlang <kiderl...@REDACTED> wrote:
> where can I get joe armstrongs book?
>
> i was not trying to speed up adding by paralell it was just trivial example
> to see if I could use erlang to paralell up my program.  and my original
> program was trying to compute average which may work paralell better than
> adding
>
> why is it not working? :(
>
> On Sat, May 30, 2009 at 2:48 AM, Ulf Wiger
> <ulf.wi...@REDACTED>wrote:
>
>
>
>
>
> > ----- "Kid Erlang" <kiderl...@REDACTED> wrote:
>
> > > hi everyone.  i am still confused?  is there a good book on
> > > ERLANG to read on how to do multi process cloud scaling?
>
> > > i do not understand your answers
>
> > Apologies for the somewhat existential rants.
>
> > You should read Joe Armstrong's book, which explains a lot
> > of things, including how to scale with Distributed Erlang
> > and multicore.
>
> > If you use Distributed Erlang, that is, many Erlang nodes
> > connected in the most natural Erlang way, you will simply
> > use processes and message passing. When using sockets, you
> > can write a module similar to the rpc module, but which
> > calls term_to_binary(Data) before sending the request to
> > the socket, and binary_to_term(Bin) on the response coming
> > back (and vice versa on the other end). It is reasonably
> > straightforward. Joe's book has a chapter (ch 14) on
> > socket programming, which pretty much spells out how to
> > do this.
>
> > One of the new problems with clouds is how host names can
> > come and go, making it difficult to have the kind of static
> > configuration of the members as one usually has in a cluster
> > (where one usually has full control over the IP addresses,
> > host names, etc.)
>
> > Joel Reymont used to have a blog article about setting up
> > mnesia for EC2, which AFAIR addressed these issues, but
> > the article seems to have rotted away.
>
> > I found this:
> >http://blog.onclearlake.ca/2008/03/setup-ec2-instance-with-erlang-thi...
>
> > > i want to scale into the cloud to generate bigger sets of
> > > numbers and be able to run multiple copies of my scripts which
> > > already run in a collection.
>
> > In your example, you are basically doing addition. You should
> > be aware that this form of work cannot be sped up even by
> > parallelizing on multicore. Just running through the list and
> > spawning a process (or even sending a message) is more work than
> > just performing the addition.
>
> > I showed an example of that in my Erlang Factory presentation:
>
> >http://www.erlang-factory.com/upload/presentations/56/UlfWiger_Erlang...
> > (slide 9 shows some simple benchmark figures on two different
> > types of jobs being parallelized.)
>
> > BR,
> > Ulf W
> > --
> > Ulf Wiger
> > CTO, Erlang Training & Consulting Ltd.
> >http://www.erlang-consulting.com