Re: [Boost-bugs] [Boost C++ Libraries] #7906: Very bad performance of generic implementation of shared_mutex on windows

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7906: Very bad performance of generic implementation of shared_mutex on windows
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-02-12 05:01:08

#7906: Very bad performance of generic implementation of shared_mutex on windows
-------------------------------------------+--------------------------------
  Reporter:  Andrey <nikolay@…>            |       Owner:  viboes             
      Type:  Bugs                          |      Status:  assigned           
 Milestone:  To Be Determined              |   Component:  thread             
   Version:  Boost 1.52.0                  |    Severity:  Optimization       
Resolution:                                |    Keywords:  thread shared_mutex
-------------------------------------------+--------------------------------

Comment (by Andrey <nikolay@…>):

 Results (average for 5 runs) on my new PC:

 shared_mutex_speed_win32_no_patch:
 Time spent:1910861 nanoseconds

 shared_mutex_speed_generic_no_patch:
 Time spent:6831144 nanoseconds

 shared_mutex_speed_win32_patch:
 Time spent:1969341 nanoseconds

 shared_mutex_speed_generic_patch:
 Time spent:6782312 nanoseconds

 shared_mutex_speed_generic_patch_no_interruptions (defined
 BOOST_THREAD_DONT_PROVIDE_INTERRUPTIONS):
 Time spent:6798547 nanoseconds

 shared_mutex_speed_win32_patch_no_interruptions (defined
 BOOST_THREAD_DONT_PROVIDE_INTERRUPTIONS):
 Time spent:1998582 nanoseconds


 In generic implementation most of CPU time is spent on
 boost::mutex::scoped_lock lk(state_change);. Win32 implementation is lock
 free and it is a reason why this implementation is very fast.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7906#comment:9>
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