08-15-2008
compilation parameters, code optimization
Hi all,
I implemented an application, through using c++ and compiled it with g++.
At first, what I did is (@ compilation):
g++ calcBacon.C -o test -DDEBUG
after I ran my application it took almost 120 sec. to finish its execution
when I compiled with optimization parameters, execution time dramatically changed
what I did was:
g++ calcBacon.C -o test -O3 -DDEBUG
after this compilation overall execution took 35 sec. to finish.
It is a big difference (~85secs)...
My questions:
1) Is it related with my implementation? I mean, is my implementation so bad, therefore compiler optimization responds very good to my code? (is this the explanation?).
2) Do you know any other optimization parameter like this? Could you please explain in what cases they work good?
Thanks in advance
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LEARN ABOUT REDHAT
scroll
curs_scroll(3X) curs_scroll(3X)
NAME
scroll, scrl, wscrl - scroll a curses window
SYNOPSIS
#include <curses.h>
int scroll(WINDOW *win);
int scrl(int n);
int wscrl(WINDOW *win, int n);
DESCRIPTION
The scroll routine scrolls the window up one line. This involves moving the lines in the window data structure. As an optimization, if
the scrolling region of the window is the entire screen, the physical screen may be scrolled at the same time.
For positive n, the scrl and wscrl routines scroll the window up n lines (line i+n becomes i); otherwise scroll the window down n lines.
This involves moving the lines in the window character image structure. The current cursor position is not changed.
For these functions to work, scrolling must be enabled via scrollok.
RETURN VALUE
These routines return ERR upon failure, and OK (SVr4 only specifies "an integer value other than ERR") upon successful completion.
NOTES
Note that scrl and scroll may be macros.
The SVr4 documentation says that the optimization of physically scrolling immediately if the scroll region is the entire screen "is" per-
formed, not "may be" performed. This implementation deliberately does not guarantee that this will occur, to leave open the possibility of
smarter optimization of multiple scroll actions on the next update.
Neither the SVr4 nor the XSI documentation specify whether the current attribute or current color-pair of blanks generated by the scroll
function is zeroed. Under this implementation it is.
PORTABILITY
The XSI Curses standard, Issue 4 describes these functions.
SEE ALSO
curses(3X), curs_outopts(3X)
curs_scroll(3X)