Ruby

# IO#wait performance

require "io/wait"

r, w = IO.pipe

w.syswrite '.'

nr = 1000000

nr.times {

r.wait

}

# IO#wait performance. worst case of single fd.

require "io/wait"

ios = []

nr = 1000000

max = Process.getrlimit(Process::RLIMIT_NOFILE)[0]

puts "max fd: #{max} (results not apparent with <= 1024 max fd)"

((max / 2) - 11).times do

ios.concat IO.pipe

end

r, w = IO.pipe

w.syswrite '.'

puts "last IO: #{r.inspect}"

nr.times do

r.wait

end