Re: [Boost-bugs] [Boost C++ Libraries] #7422: Provide a condition variable with zero-overhead performance penality

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7422: Provide a condition variable with zero-overhead performance penality
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-12-18 21:26:58

#7422: Provide a condition variable with zero-overhead performance penality
------------------------------------------+---------------------------------
  Reporter:  maxim.yegorushkin@…          |       Owner:  viboes            
      Type:  Feature Requests             |      Status:  assigned          
 Milestone:  To Be Determined             |   Component:  thread            
   Version:  Boost 1.51.0                 |    Severity:  Regression        
Resolution:                               |    Keywords:  condition_variable
------------------------------------------+---------------------------------

Comment (by viboes):

 Replying to [comment:29 Maxim Yegorushkin <maxim.yegorushkin@…>]:
 > With this patch boost::condition_variable performs better than std one
 in the benchmark:
 >
 > {{{
 > consumers,(std-boost)/std,std,boost
 > 1,1.738797,17452356,17148895
 > 2,0.818735,26905168,26684886
 > 3,0.909335,58318561,57788250
 > 4,0.929148,45236280,44815968
 > 5,1.255012,54510018,53825911
 > 6,1.410902,63880220,62978933
 > 7,1.094065,72988694,72190150
 > 8,1.073388,82271239,81388149
 > 9,0.915663,91362805,90526230
 > 10,0.991684,100724122,99725257
 > }}}
 >
 > (I also updated that spreadsheet on docs.google.com)
 >
 > Nicely done!

 Glad to see these nice figures ;-)

 > In the patch condition_variable always has internal_mutex member, is it
 intended?

 No. I left it to preserve the layout of condition_variable in case I reach
 to be able to have a single library able to manage with both
 configurations, but it needs a lot of changes. So for the time been, users
 will need a build the library with
 -DBOOST_THREAD_DONT_PROVIDE_INTERRUPTIONS and internal_mutex will not be
 defined.

 I appreciate a lot this long walk co-working with you to achieve these
 results, that I hope are good enough for your application.

 I will commit it as soon as all the regression test pass and I hope I
 would be able to merge it the release 1.53.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7422#comment:30>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.