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#!/usr/bin/env ruby
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
$: << File.expand_path('../../lib', __FILE__)
require 'optparse'
require 'thread'
require 'benchmark'
require 'atomic'
Thread.abort_on_exception = true
$conf = {
:lock => "atomic",
:num_threads => 100,
:count => 100_000,
:count_per_thread => nil,
:slow => nil,
}
OptionParser.new do |opts|
opts.on("-c", "--count NUM") do |n|
$conf[:count] = n.to_i
end
opts.on("-p", "--count-per-thread") do |n|
$conf[:count_per_thread] = n.to_i
end
opts.on("-t", "--num-threads NUM") do |n|
$conf[:num_threads] = n.to_i
end
opts.on("-s", "--slow NUM") do |n|
$conf[:slow] = n.to_i
end
opts.on("-l", "--lock atomic|mutex") do |x|
$conf[:lock] = x
end
opts.on("-h", "--help"){ puts opts; exit }
end.parse!(ARGV)
unless $conf[:count_per_thread]
$conf[:count_per_thread] = $conf[:count] / $conf[:num_threads]
end
$conf.delete(:count)
if $conf[:slow].to_i > 0
require 'digest/md5'
def slow_down
$conf[:slow].times do |i|
Digest::MD5.hexdigest(i.to_s)
end
end
ret = []
10.times do
m = Benchmark.measure{ slow_down }
ret << m.real
end
$conf[:slow_time] = [ret.min, ret.max]
else
def slow_down; end
end
$stderr.puts $conf.inspect
def para_prepare(&block)
num_threads = $conf[:num_threads]
count = $conf[:count_per_thread]
if num_threads % 2 > 0
raise ArgumentError, "num_threads must be a multiple of two"
end
# Keep those threads together
tg = ThreadGroup.new
num_threads.times do |i|
diff = (i % 2 == 0) ? 1 : -1
t = Thread.new do
nil until $go
count.times do
yield diff
end
end
tg.add(t)
end
# Make sure all threads are started
while tg.list.find{|t| t.status != "run"}
Thread.pass
end
# For good measure
GC.start
$go = false
tg
end
$tg = nil
if $conf[:lock] == "atomic"
$atom = Atomic.new(0)
$tg = para_prepare do |diff|
$atom.update do |x|
slow_down
x + diff
end
end
else
$lock = Mutex.new
$value = 0
$tg = para_prepare do |diff|
$lock.synchronize do
slow_down
$value += diff
end
end
end
# Run !
#
# NOTE: It seems to me that this measurement method
# is sensible to how the system dispatches his resources.
#
# More precise caluclation could be done using
# getrusage's times
ret = Benchmark.measure do
$go = true
$tg.list.each{|t| t.join}
$go = false
end
puts ret.real
|
