Re: STL Slow - VS2005

From:

"Bo Persson" <bop@gmb.dk>

Newsgroups:

microsoft.public.vc.stl

Date:

Sat, 19 Aug 2006 12:38:03 +0200

Message-ID:

<4ko804Fd38esU1@individual.net>

"Jerry Coffin" <jcoffin@taeus.com> skrev i meddelandet
news:MPG.1f502d18e96112c89896d5@news.sunsite.dk...

In article <F15505AE-1D5A-4DAF-A294-FE2CF4F2B3EC@microsoft.com>,
WXS@discussions.microsoft.com says...

Here is the file that was tested with vs2005 stl and vs2005
w/stlport 5.0

The first and most crucial question to ask of any benchmark is how
accurately this benchmark represents real-world workloads. Unless
the
benchmark is quite close to real-world usage, it's meaningless --
and
even if it's fairly close, it can still be entirely meaningless (if
the
differences between "fairly close" and "real world" make a big
difference in performance).

[ ... ]

string s ;
for ( int i = 0 ; i < 100000000; ++ i ) {
s += " " ;

This one is especially funny, as a small change into

s += ' ';

makes it run *a lot* faster.

What realistic application is doing a significant number of append
with single character string literals?

Bo Persson