source code
# The Computer Language Benchmarks Game
# https://salsa.debian.org/benchmarksgame-team/benchmarksgame/
#
# contributed by Jesse Millikan
# Modified by Wesley Moxam
# Modified && Parallelised by Scott Leggett
# *reset*
# Thread.exclusive deprecated
require 'thread'
module MiniParallel
class Worker
def initialize(read, write)
@read, @write = read, write
end
def close_pipes
@read.close
@write.close
end
def work(index)
Marshal.dump(index, @write)
Marshal.load(@read)
end
end
def self.map(array, &block)
work_in_processes(
array,
[array.size, core_count].min,
&block
)
end
def self.core_count
@@core_count ||= IO.read("/proc/cpuinfo").scan(/^processor/).size
end
private
def self.work_in_processes(array, count, &block)
index = -1
results, threads = [], []
mx = Mutex.new
workers = create_workers(array, count, &block)
workers.each do |worker|
threads << Thread.new do
loop do
mx.synchronize do index += 1 end
break if index >= array.size
results[index] = worker.work(index)
end
worker.close_pipes
end
end
threads.each(&:join)
Process.waitall
results
end
def self.create_workers(array, count, &block)
workers = []
count.times do
workers << create_worker(array, workers, &block)
end
workers
end
def self.create_worker(array, started_workers, &block)
child_read, parent_write = IO.pipe
parent_read, child_write = IO.pipe
Process.fork do
started_workers.each(&:close_pipes)
parent_write.close
parent_read.close
process_incoming_jobs(child_read, child_write, array, &block)
child_read.close
child_write.close
end
child_read.close
child_write.close
Worker.new(parent_read, parent_write)
end
def self.process_incoming_jobs(read, write, array, &block)
until read.eof?
index = Marshal.load(read)
Marshal.dump(block.call(array[index]), write)
end
end
end
def item_check(left, right)
if left
1 + item_check(*left) + item_check(*right)
else
1
end
end
def bottom_up_tree(depth)
if depth > 0
depth -= 1
[bottom_up_tree(depth), bottom_up_tree(depth)]
else
[nil, nil]
end
end
max_depth = ARGV[0].to_i
min_depth = 4
max_depth = [min_depth + 2, max_depth].max
stretch_depth = max_depth + 1
stretch_tree = bottom_up_tree(stretch_depth)
puts "stretch tree of depth #{stretch_depth}\t check: #{item_check(*stretch_tree)}"
stretch_tree = nil
long_lived_tree = bottom_up_tree(max_depth)
if MiniParallel.core_count > 1
MiniParallel.map(min_depth.step(max_depth, 2).to_a) do |depth|
iterations = 2**(max_depth - depth + min_depth)
check = 0
(1..iterations).each do |i|
check += item_check(*bottom_up_tree(depth))
end
"#{iterations}\t trees of depth #{depth}\t check: #{check}"
end.each{|l| puts l}
else
min_depth.step(max_depth, 2).each do |depth|
iterations = 2**(max_depth - depth + min_depth)
check = 0
(1..iterations).each do |i|
check += item_check(*bottom_up_tree(depth))
end
puts "#{iterations}\t trees of depth #{depth}\t check: #{check}"
end
end
puts "long lived tree of depth #{max_depth}\t check: #{item_check(*long_lived_tree)}"
notes, command-line, and program output
NOTES:
64-bit Ubuntu quad core
ruby 3.3.5
(2024-09-03
revision ef084cc8f4)
+YJIT [x86_64-linux]
Wed, 04 Sep 2024 18:16:09 GMT
COMMAND LINE:
/opt/src/ruby-3.3.5/bin/ruby --yjit -W0 binarytrees.ruby-5.ruby 21
PROGRAM OUTPUT:
stretch tree of depth 22 check: 8388607
2097152 trees of depth 4 check: 65011712
524288 trees of depth 6 check: 66584576
131072 trees of depth 8 check: 66977792
32768 trees of depth 10 check: 67076096
8192 trees of depth 12 check: 67100672
2048 trees of depth 14 check: 67106816
512 trees of depth 16 check: 67108352
128 trees of depth 18 check: 67108736
32 trees of depth 20 check: 67108832
long lived tree of depth 21 check: 4194303