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 20:04:30

#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           |  
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Comment(by yuri_goldfeld@…):

 Hmm.  Well, I did my best by providing data, which you may or may not act
 upon; certainly I'm not suggesting it's easy.  The arguments above you put
 forth are sound in their own way, however from a practical (as opposed to
 theoretical) standpoint these are still serious issues.  Simply put, if an
 implementation is 2-30 times slower than expected on one of the most
 popular compiler/hardware combinations out there, this is a problem.  Of
 course, it sucks for you to have to figure out what the compiler is doing
 wrong in its optimizations or whatever... but the practical result remains
 the practical result and is really all that matters to the user.

 I'm not saying there is a design flaw or anything or that the Boost spirit
 is violated, just that there is a usability problem in some very popular
 environments.

 Also, while you say "the" bottleneck is locales, I reiterate that this is
 only true for case-insensitive things I ran; you can see that the case-
 sensitive algorithms (at least some of them) are also significantly slower
 (2+ times in my runs above), just not to the same extreme extent.  It
 would be fairly easy to try out more, if desired.

 At least, I would personally recommend you add a Performance section to
 the StringAlgo documentation referring to some of these potential
 pitfalls.  This may help people in practical terms.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3218#comment:10>
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