Re: [Gnu-arch-users] hackerlab str_ functions performance

[Andrew Suffield]

On Fri, Sep 03, 2004 at 01:00:40PM +0200, Yann Droneaud wrote:
> Jani Monoses <address@hidden> writes:
> 
> > Hello
> >
> > hackerlab's str_cmp, str_length and str_cpy are among the top CPU users when
> > running changes and inventory at least, totalling 40% of tla cpu time.
> >     
> >         %
> > 14664    20.3263  str_cmp
> > 9685     13.4247  str_length
> > 9178     12.7220  is_simple_anchored_regexp
> > 5442      7.5434  rx_dfa_advance_to_final
> > 5265      7.2980  str_cpy
> >
> > a similar topic was raised a while ago related to mem_set0.
> > This crude patch changes them to calling glibc's routines and yields about a
> > 15-20% speedup(not much) 
> >
> 
> compete against inline and assembler optimised functions is quite hard :/

The glibc routines are written in C, although they are
inlined. They're really quite evil, and beat the crap out of a generic
assembly routine. They're designed so that the compiler can select an
appropriate strategy based on its knowledge of the data and the target
processor.

-- 
  .''`.  ** Debian GNU/Linux ** | Andrew Suffield
 : :' :  http://www.debian.org/ |
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