run_with_fork
Some simple parallelism for Crystal. Run some heavy or blocked thread operations in background fork. Fork created for every new task and exit when done.
Installation
Add this to your application's shard.yml:
dependencies:
run_with_fork:
github: kostya/run_with_forkUsage
require "run_with_fork"
require "digest/md5"
def heavy_operation(str)
1000.times { str = Digest::MD5.hexdigest(str) }
str
end
pid, read_io = Process.run_with_fork do |write_io|
write_io.puts heavy_operation("bla")
end
res = read_io.gets
read_io.close
puts resExample concurrent
without fork:
crystal examples/2.cr --release -- 100 10000 0
00:00:03.380020000
with fork:
crystal examples/2.cr --release -- 100 10000 1
00:00:00.758754000
require "run_with_fork"
require "digest/md5"
t = Time.now
res = Channel(String).new
times = (ARGV[0]? || 100).to_i
count = (ARGV[1]? || 10000).to_i
use_fork = (ARGV[2]? == "1")
puts "use #{use_fork ? "fork" : "fiber"}"
def operation(count, data)
s = ""
count.times do
s = Digest::MD5.hexdigest("#{data} bla #{s}")
end
"done #{data} #{s}"
end
times.times do |i|
spawn do
if use_fork
pid, r = Process.run_with_fork do |w|
w.puts operation(count, i)
end
s = r.gets
r.close
res.send s.not_nil!
else
res.send operation(count, i)
end
end
end
times.times do
p res.receive
end
p Time.now - tExample use msgpack to exchange data
require "run_with_fork"
require "msgpack"
pid, read_io = Process.run_with_fork do |write_io|
1.to_msgpack(write_io)
"done".to_msgpack(write_io)
[1, 2, 3].to_msgpack(write_io)
end
pull = MessagePack::Unpacker.new(read_io)
p pull.read_uint # => 1_u8
p pull.read_string # => "done"
p Array(Int32).new(pull) # => [1, 2, 3]
read_io.close