[ANN] forkoff-0.0.4

NAME

   forkoff

SYNOPSIS

   brain-dead simple parallel processing for ruby

URI

   http://rubyforge.org/projects/codeforpeople

INSTALL

   gem install forkoff

DESCRIPTION

   forkoff works for any enumerable object, iterating a code block to  
run in a
   child process and collecting the results.  forkoff can limit the  
number of
   child processes which is, by default, 2.

HISTORY
   0.0.4
     - code re-org
     - add :strategy option
     - default number of processes is 2, not 8


SAMPLES

   <========< samples/a.rb >========>

   ~ > cat samples/a.rb

     # forkoff makes it trivial to do parallel processing with ruby,  
the following
     # prints out each word in a separate process
     #

       require 'forkoff'

       %w( hey you ).forkoff!{|word| puts "#{ word } from  
#{ Process.pid }"}

   ~ > ruby samples/a.rb

     hey from 1032
     you from 1033


   <========< samples/b.rb >========>

   ~ > cat samples/b.rb

     # for example, this takes only 4 seconds or so to complete (8  
iterations
     # running in two processes = twice as fast)
     #

       require 'forkoff'

       a = Time.now.to_f

       results =
         (0..7).forkoff do |i|
           sleep 1
           i ** 2
         end

       b = Time.now.to_f

       elapsed = b - a

       puts "elapsed: #{ elapsed }"
       puts "results: #{ results.inspect }"

   ~ > ruby samples/b.rb

     elapsed: 4.25545883178711
     results: [0, 1, 4, 9, 16, 25, 36, 49]


   <========< samples/c.rb >========>

   ~ > cat samples/c.rb

     # forkoff does *NOT* spawn processes in batches, waiting for each  
batch to
     # complete.  rather, it keeps a certain number of processes busy  
until all
     # results have been gathered.  in otherwords the following will  
ensure that 3
     # processes are running at all times, until the list is complete.  
note that
     # the following will take about 3 seconds to run (3 sets of 3 @ 1  
second).
     #

     require 'forkoff'

     pid = Process.pid

     a = Time.now.to_f

     pstrees =
       %w( a b c d e f g h i ).forkoff! :processes => 3 do |letter|
         sleep 1
         { letter => ` pstree -l 2 #{ pid } ` }
       end


     b = Time.now.to_f

     puts
     puts "pid: #{ pid }"
     puts "elapsed: #{ b - a }"
     puts

     require 'yaml'

     pstrees.each do |pstree|
       y pstree
     end

   ~ > ruby samples/c.rb


     pid: 1048
     elapsed: 3.14415812492371

     ---
     a: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01049 ahoward ruby -Ilib samples/c.rb
        |-+- 01050 ahoward ruby -Ilib samples/c.rb
        \-+- 01051 ahoward ruby -Ilib samples/c.rb

     ---
     b: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01049 ahoward (ruby)
        |-+- 01050 ahoward ruby -Ilib samples/c.rb
        \-+- 01051 ahoward ruby -Ilib samples/c.rb

     ---
     c: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01049 ahoward ruby -Ilib samples/c.rb
        |-+- 01050 ahoward ruby -Ilib samples/c.rb
        \-+- 01051 ahoward ruby -Ilib samples/c.rb

     ---
     d: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01061 ahoward ruby -Ilib samples/c.rb
        |-+- 01062 ahoward ruby -Ilib samples/c.rb
        \-+- 01063 ahoward ruby -Ilib samples/c.rb

     ---
     e: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01061 ahoward (ruby)
        |-+- 01062 ahoward ruby -Ilib samples/c.rb
        \-+- 01063 ahoward ruby -Ilib samples/c.rb

     ---
     f: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01061 ahoward ruby -Ilib samples/c.rb
        |-+- 01062 ahoward ruby -Ilib samples/c.rb
        \-+- 01063 ahoward ruby -Ilib samples/c.rb

     ---
     g: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01090 ahoward ruby -Ilib samples/c.rb
        |-+- 01091 ahoward ruby -Ilib samples/c.rb
        \-+- 01092 ahoward ruby -Ilib samples/c.rb

     ---
     h: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01090 ahoward ruby -Ilib samples/c.rb
        |-+- 01091 ahoward ruby -Ilib samples/c.rb
        \-+- 01092 ahoward ruby -Ilib samples/c.rb

     ---
     i: |
       -+- 01048 ahoward ruby -Ilib samples/c.rb
        |-+- 01090 ahoward ruby -Ilib samples/c.rb
        |-+- 01091 ahoward ruby -Ilib samples/c.rb
        \-+- 01092 ahoward ruby -Ilib samples/c.rb



   <========< samples/d.rb >========>

   ~ > cat samples/d.rb

     # forkoff supports two strategies of reading the result from the  
child: via
     # pipe (the default) or via file.  you can select which to use  
using the
     # :strategy option.
     #

       require 'forkoff'

       %w( hey you guys ).forkoff :strategy => :file do |word|
         puts "#{ word } from #{ Process.pid }"
       end

   ~ > ruby samples/d.rb

     hey from 1102
     you from 1103
     guys from 1104




a @ http://codeforpeople.com/
--
we can deny everything, except that we have the possibility of being  
better. simply reflect on that.
h.h. the 14th dalai lama