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: 2009-07-18 16:48:42

#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 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
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3218#comment:6>
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