Re: [Boost-bugs] [Boost C++ Libraries] #3218: string_algo algorithms are quite slow in some popular compiler/OS/hardware situations

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #3218: string_algo algorithms are quite slow in some popular compiler/OS/hardware situations
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-07-20 19:17:46

#3218: string_algo algorithms are quite slow in some popular compiler/OS/hardware
situations
------------------------------------------------------+---------------------
 Reporter:  Yuri Goldfeld <yuri_goldfeld@…>           |       Owner:  pavol_droba
     Type:  Bugs                                      |      Status:  new        
Milestone:  To Be Determined                          |   Component:  string_algo
  Version:  Boost 1.37.0                              |    Severity:  Problem    
 Keywords:  performance string_algo strings           |  
------------------------------------------------------+---------------------

Comment(by anonymous):

 Replying to [comment:6 steven_watanabe]:
 > I just ran a few tests using a custom case insensitive comparison
 predicate.
 >
 > {{{
 > struct iequal_pred {
 >     bool operator()(char c1, char c2) const {
 >         return(std::tolower(c1) == std::tolower(c2));
 >     }
 > };
 > }}}
 >
 > The results look a lot better.
 >
 > {{{
 > StartsWithI(string("abcdefghi"), "aBcD")| 349 msec.
 > starts_with(string("abcdefghi"), "aBcD", iequal_pred())| 706 msec.
 > Boost/hand ratio = 2.02292
 >
 > EqualsI("abcdefghi", "aBcDeFgHi")| 188 msec.
 > equals("abcdefghi", "aBcDeFgHi", iequal_pred())| 262 msec.
 > Boost/hand ratio = 1.39362
 > }}}

 Hello, thanks for the testing. It seems that MS locates implementation is
 realy the cause of problems. In your test, you have used C-locales which
 are probably much faster

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3218#comment:8>
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