why my c++ program call so many time of _fini

[fanasy]

my platform is
linux 2.6.9-55.ELsmp

I use gprof to analyse my c++ program for speed up.
but I find 69.65% time to call _fini and the calls is 12308332.
I google the meaning of _fini which is for libc.
Is there any common method to reduce the call time of _fini?
my program is so long that I can't show here.

my program use many stl lib and almost 8,000,000 objects,many strings, and string find.

thanks!

[roberts]

It looks like you're creating and destroying a lot of objects.

5.2. Library constructor and destructor functions

Libraries should export initialization and cleanup routines using the gcc __attribute__((constructor)) and __attribute__((destructor)) function attributes. See the gcc info pages for information on these. Constructor routines are executed before dlopen returns (or before main() is started if the library is loaded at load time). Destructor routines are executed before dlclose returns (or after exit() or completion of main() if the library is loaded at load time). The C prototypes for these functions are:

void __attribute__ ((constructor)) my_init(void);
void __attribute__ ((destructor)) my_fini(void);

Shared libraries must not be compiled with the gcc arguments ``-nostartfiles'' or ``-nostdlib''. If those arguments are used, the constructor/destructor routines will not be executed (unless special measures are taken).

5.2.1. Special functions _init and _fini (OBSOLETE/DANGEROUS)

Historically there have been two special functions, _init and _fini that can be used to control constructors and destructors. However, they are obsolete, and their use can lead to unpredicatable results. Your libraries should not use these; use the function attributes constructor and destructor above instead.

If you must work with old systems or code that used _init or _fini, here's how they worked. Two special functions were defined for initializing and finalizing a module: _init and _fini. If a function ``_init'' is exported in a library, then it is called when the library is first opened (via dlopen() or simply as a shared library). In a C program, this just means that you defined some function named _init. There is a corresponding function called _fini, which is called whenever a client finishes using the library (via a call dlclose() that brings its reference count to zero, or on normal exit of the program). The C prototypes for these functions are:

void _init(void);
void _fini(void);

In this case, when compiling the file into a ``.o'' file in gcc, be sure to add the gcc option ``-nostartfiles''. This keeps the C compiler from linking the system startup libraries against the .so file. Otherwise, you'll get a ``multiple-definition'' error. Note that this is completely different than compiling modules using the recommended function attributes. My thanks to Jim Mischel and Tim Gentry for their suggestion to add this discussion of _init and _fini, as well as help in creating it.

Without code, it's hard to say where optimizations can go.

[fanasy]

thanks roberts for remind.
I drop the object to string.
now can't see the fini call.
solved.