Using STL in large project
Alex Vinokur
"Jorge" <cafelit...@yahoo.com> wrote:
> Hi:
>
> We're thinking about use sgi's STL in a really large project.
> Process speed it's very important for this project and since I've
> only tried STL in little projects, I've got no idea how a very large
> data set will affect a STL project based.
>
> what do you think about?
>
> thanks in advance
> Jorge
>
>
Hi,
Here are some aspects of comparative analisis
of STL and Standard C Library.
The following functions (methods, operators) were measured.
----------------------------------------------------
Standard C Library | STL
----------------------------------------------------
strcpy | operator= (string)
strcat | operator+= (string)
strlen | size () (string)
char* | constructor&destructor (string)
char-array | constructor&destructor (string)
malloc&free | new&delete (string)
(malloc+init)&free | new&delete (string)
----------------------------------------------------
Average time-cost of execution was obtained.
Here are the results of the experiment.
//##########################################################################
//################# Results of the experiment ##############################
// SunOS 5.6 Generic_105181-09 sun4m sparc SUNW,SPARCstation-5
// g++ version 2.8.1
//##########################################################################
##### Test#1 #####
Test#1 [strcpy() ] : Average time = 890 nsec
Test#1 [STL : operator=] : Average time = 515 nsec
Test#1 [strcat() ] : Average time = 86770 nsec
Test#1 [STL : operator+=] : Average time = 4682 nsec
Test#1 [strlen() ] : Average time = 98352 nsec
Test#1 [STL : size () ] : Average time = 286 nsec
Test#1 [char*] : Average time = 133 nsec
Test#1 [char-array] : Average time = 751 nsec
Test#1 [STL : constructor&destructor] : Average time = 3226 nsec
Test#1 [malloc&free] : Average time = 4735 nsec
Test#1 [(malloc+init)&free] : Average time = 4573 nsec
Test#1 [STL : new&delete] : Average time = 6947 nsec
##### Test#2 #####
Test#2 [strcpy() ] : Average time = 678 nsec
Test#2 [STL : operator=] : Average time = 521 nsec
Test#2 [strcat() ] : Average time = 83619 nsec
Test#2 [STL : operator+=] : Average time = 2485 nsec
Test#2 [strlen() ] : Average time = 97888 nsec
Test#2 [STL : size () ] : Average time = 286 nsec
Test#2 [char*] : Average time = 131 nsec
Test#2 [char-array] : Average time = 750 nsec
Test#2 [STL : constructor&destructor] : Average time = 3604 nsec
Test#2 [malloc&free] : Average time = 4070 nsec
Test#2 [(malloc+init)&free] : Average time = 5863 nsec
Test#2 [STL : new&delete] : Average time = 6867 nsec
##### Test#3 #####
Test#3 [strcpy() ] : Average time = 679 nsec
Test#3 [STL : operator=] : Average time = 523 nsec
Test#3 [strcat() ] : Average time = 88326 nsec
Test#3 [STL : operator+=] : Average time = 2426 nsec
Test#3 [strlen() ] : Average time = 135749 nsec
Test#3 [STL : size () ] : Average time = 287 nsec
Test#3 [char*] : Average time = 131 nsec
Test#3 [char-array] : Average time = 826 nsec
Test#3 [STL : constructor&destructor] : Average time = 3059 nsec
Test#3 [malloc&free] : Average time = 4066 nsec
Test#3 [(malloc+init)&free] : Average time = 4809 nsec
Test#3 [STL : new&delete] : Average time = 7244 nsec
##### Test#4 #####
Test#4 [strcpy() ] : Average time = 846 nsec
Test#4 [STL : operator=] : Average time = 521 nsec
Test#4 [strcat() ] : Average time = 88333 nsec
Test#4 [STL : operator+=] : Average time = 2424 nsec
Test#4 [strlen() ] : Average time = 102409 nsec
Test#4 [STL : size () ] : Average time = 286 nsec
Test#4 [char*] : Average time = 132 nsec
Test#4 [char-array] : Average time = 751 nsec
Test#4 [STL : constructor&destructor] : Average time = 3060 nsec
Test#4 [malloc&free] : Average time = 4142 nsec
Test#4 [(malloc+init)&free] : Average time = 4490 nsec
Test#4 [STL : new&delete] : Average time = 7092 nsec
##### Test#5 #####
Test#5 [strcpy() ] : Average time = 845 nsec
Test#5 [STL : operator=] : Average time = 887 nsec
Test#5 [strcat() ] : Average time = 88568 nsec
Test#5 [STL : operator+=] : Average time = 2421 nsec
Test#5 [strlen() ] : Average time = 104744 nsec
Test#5 [STL : size () ] : Average time = 286 nsec
Test#5 [char*] : Average time = 130 nsec
Test#5 [char-array] : Average time = 751 nsec
Test#5 [STL : constructor&destructor] : Average time = 3058 nsec
Test#5 [malloc&free] : Average time = 4138 nsec
Test#5 [(malloc+init)&free] : Average time = 4489 nsec
Test#5 [STL : new&delete] : Average time = 7026 nsec
//##########################################################################
For more details please see the threads titeled
1) "STL and Usual C : Average time-cost of execution"
in comp.lang.c++.moderated,
comp.lang.c++
The link is :
http://x11.dejanews.com/dnquery.xp?search=thread&svcclass=dnserver&threaded=1
&ST=PS&CONTEXT=914841639.1172307970&HIT_CONTEXT=914841639.1172307970&HIT_NUM=
19&recnum=%3c36822F3...@tibam.elex.co.il%3e%231/3
2) "Corrected and Supplemented -> Re: STL and Usual C :
Average time-cost of execution"
in comp.lang.c++.moderated,
comp.lang.c++
The link is :
http://x14.dejanews.com/dnquery.xp?search=thread&svcclass=dnserver&threaded=1
&ST=PS&CONTEXT=914915711.1193541737&HIT_CONTEXT=914915711.1193541737&HIT_NUM=
0&recnum=%3c368734F...@tibam.elex.co.il%3e%231/3
//##########################################################################
I think you need to evaluate several aspects
regarding performance (computional complexity)
of STL and Standatd C Library
and to do them comparative analysis.
Alex
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