# one thread, one mutex (no contention)

require 'thread'
m = Mutex.new
r = 0
max = 2000
lmax = max * max
(1..1).map{
  Thread.new{
    i = 0
    while i<lmax
      i += 1
      m.synchronize{
        r += 1
      }
    end
  }
}.each{|e|
  e.join
}
raise r.to_s if r != max * max
>
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<div class='path'>path: <a href='/ruby.git/log/?h=v1_1b9_31&amp;id=6dfaccf20da5deefe66221df8b4d95c68dfbe233'>root</a>/<a href='/ruby.git/log/tool?h=v1_1b9_31&amp;id=6dfaccf20da5deefe66221df8b4d95c68dfbe233'>tool</a>/<a href='/ruby.git/log/tool/colorize.rb?h=v1_1b9_31&amp;id=6dfaccf20da5deefe66221df8b4d95c68dfbe233'>colorize.rb</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/ruby.git/log/tool/colorize.rb?h=v1_1b9_31&amp;id=6dfaccf20da5deefe66221df8b4d95c68dfbe233&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2017-10-14 02:17:07 +0000'>2017-10-14</span></td><td><a href='/ruby.git/commit/tool/colorize.rb?h=v1_1b9_31&amp;id=25aec0b8352428871b97de41f7da9abff1ab7d90'>distinguish pass and fail by highlight [ci skip]</a></td><td>nobu</td></tr>
<tr><td><span title='2017-06-15 02:39:06 +0000'>2017-06-15</span></td><td><a href='/ruby.git/commit/tool/colorize.rb?h=v1_1b9_31&amp;id=d25ed18c3defab09e71318baca5037541728c877'>make-snapshot: colorize [ci skip]</a></td><td>nobu</td></tr>
<tr><td><span title='2017-04-21 03:01:12 +0000'>2017-04-21</span></td><td><a href='/ruby.git/commit/tool/colorize.rb?h=v1_1b9_31&amp;id=bdc6d41640f07d260b66eaaeea38145789227513'>ext/extmk.rb: colorize notes [Feature #13302]</a></td><td>nobu</td></tr>