From owner-freebsd-questions  Wed May 10 23:50:35 2000
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Date: Thu, 11 May 2000 03:45:06 +0000
From: Gustavo Vieira Goncalves Coelho Rios <kernel@tdnet.com.br>
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Subject: small program is eating my memory.
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While playing a little bit with C, i realized that even small C programs
eat too much memory.
May you, kindly, explaim me what is happenning?  How can i optimize it?
I think here is eating too much memory.

a.c listing....

#include <stdio.h>
#include <unistd.h>
#include <string.h>

enum { T_SLICE = 10000 };

int
main(int argc, char *argv[])
{
        unsigned int c;
        unsigned int d;
        unsigned int v;

        if (!*++argv) {
                printf("usage: %s <1/100 seconds>\n", *--argv);
                fflush(stdout);
                return 1;
        }
        v = atoi(*argv);
        c = 0x7c2f2d5c;
        d = 0x7c5c2d2f;

        printf("Useless program (by grios): ...%c", c);

        fclose(stdin);
        fclose(stderr);

        for (;;) {
                c = c << 8 | c >> 24;
                printf("\b%c", c);
                fflush(stdout);
                usleep(v * T_SLICE);
        }
        return 0;
}

---end listing a.c

How did i compiled: cc -ansi -pedantic -Wall -s a.c
after running it, here is what i got:
$ ps aux | grep a.out
grios  90285  0.0  0.4   816  448  p1  SN+   3:42AM   0:00.16 ./a.out 1

It resident size is about 816K and is resident around 448!
Why such a small program eats so much memory?

Thank you for your time and cooperation.



-- 
"Sometimes I worry about being a success in a mediocre world."
		-- Lily Tomlin


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