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[comp.lang.c++] Performance: multiple inheritance vs. single inheritance
- From: "Alex Vinokur" <alexvn at connect dot to>
- To: libstdc++ at gcc dot gnu dot org
- Date: Tue, 5 Aug 2003 20:31:30 +0300
- Subject: [comp.lang.c++] Performance: multiple inheritance vs. single inheritance
"Graham Banks" <grahambanksRemoveIfYouAreNotASpamBot@sol-digi.com> wrote in message news:bg8hfh$c47$1@newsg4.svr.pol.co.uk...
> Does using multiple inheritance introduce any more performance overhead than
> single inheritance?
>
>
Multiple inheritance vs. single inheritance
===========================================
C/C++ Performance Tests
=======================
Using C/C++ Program Perfometer
http://sourceforge.net/projects/cpp-perfometer
http://alexvn.freeservers.com/s1/perfometer.html
Environment
-----------
Windows 2000 Professional
CYGWIN_NT-5.0 1.3.22(0.78/3/2)
Intel(R) Celeron(R) CPU 1.70 GHz
GNU gcc/g++ version 3.2 20020927 (prerelease)
Compilation : No optimization
===================== Classes : BEGIN =====================
====================
Hierarchy of classes
====================
Foo0
|
|
Foo1
|
|
_____________|_____________
| |
__________|__________ |
| | |
| | |
Foo2_v1 Foo2_v2 Foo2
| | |
|___________________| |
| |
| |
Foo3_m Foo3
| |
| |
Foo4_m Foo4
=====================
Definition of classes
=====================
// --------------
class Foo0
{
public:
Foo0 () {}
};
// --------------
class Foo1 : public Foo0
{
public:
Foo1 () : Foo0 () {}
};
// --------------
class Foo2_v1 : virtual public Foo1
{
public:
Foo2_v1 () : Foo1 () {}
};
// --------------
class Foo2_v2 : virtual public Foo1
{
public:
Foo2_v2 () : Foo1 () {}
};
// --------------
class Foo2 : public Foo1
{
public:
Foo2 () : Foo1 () {}
};
// --------------
class Foo3_m : public Foo2_v1, public Foo2_v2
{
public:
Foo3_m () : Foo1 (), Foo2_v1 (), Foo2_v2 () {}
};
// --------------
class Foo3 : public Foo2
{
public:
Foo3 () : Foo2 () {}
};
// --------------
class Foo4_m : public Foo3_m
{
public:
Foo4_m () : Foo1 (), Foo3_m () {}
};
// --------------
class Foo4 : public Foo3
{
public:
Foo4 () : Foo3 () {}
};
===================== Classes : END =======================
================ Performance tests : BEGIN ================
==================
Creating instances
==================
Summary test results
====================
#----------------------------------------------------------
# Comparison : multiple inheritance vs. single inheritance
#----------------------------------------------------------
# Resource Name : user time used (via rusage)
# Resource Cost Unit : milliseconds (unsigned long long)
# Resource State Unit : timeval
#----------------------------------------------------------
: ---------------------------------------------
: Foo0 : Level-0 base class -> 9
:
: Foo1 : Level-1 single inheritance -> 13
:
: Foo2 : Level-2 single inheritance -> 20
: Foo2_v1 : Level-2 virtual inheritance -> 20
: Foo2_v2 : Level-2 virtual inheritance -> 20
:
: Foo3 : Level-3 single inheritance -> 25
: Foo3_m : Level-3 multiple inheritance -> 42
:
: Foo4 : Level-4 single inheritance -> 32
: Foo4_m : Level-4 multiple inheritance -> 45
: ---------------------------------------------
Raw Log : http://groups.google.com/groups?selm=bglcid%24q2qeg%241%40ID-79865.news.uni-berlin.de
================ Performance tests : END ==================
Regards,
=====================================
Alex Vinokur
mailto:alexvn@connect.to
http://mathforum.org/library/view/10978.html
=====================================