Memory release

nicola54 · 06-17-2005, 06:14 AM

Hello to everyone.
My question is related to the memory used on my Linux ws RedHat 9.0 that I see using top command.
After my applications are finished I do not see the memory is released.
Is this a normal behavior of the system or I need to do something to release the memory, and what about the performance of the system with the memory not released ?

Thanks to all.

nicola

nicola54 · 06-17-2005, 06:14 AM

Merged your two threads together, no need for two of them.

IBall · 06-17-2005, 06:23 AM

Linux generally does this automatically for you. It caches as much as it can in RAM, so that the performance of the system improves. When you need that memory for something else, the kernel will free it up for you.

It is perfectly normal for your RAM to be nearly full

I hope this helps
--Ian

trickykid · 06-17-2005, 06:33 AM

Why are people so fascinated in the process of their memory releasing whatever when its done so it can sit there and do nothing? I like the fact with Linux that my RAM is *actually* being used all the time.. and all of it.. just a good feeling my money didn't go to waste in buying RAM and it not being wasted by not being used..

amosf · 06-17-2005, 08:08 AM

I have 515308 and it's using 507344. Cool... But how do I get it to use the last 7964? It's getting wasted and I PAID for that!!!

reddazz · 06-17-2005, 08:51 AM

Quote:

Originally posted by amosf
I have 515308 and it's using 507344. Cool... But how do I get it to use the last 7964? It's getting wasted and I PAID for that!!!

Just start a memory hungry app. For that, Linux will even use more of your swap, giving you more value for your money.

trickykid · 06-17-2005, 11:33 AM

Quote:

Originally posted by reddazz
Just start a memory hungry app. For that, Linux will even use more of your swap, giving you more value for your money.

Mmmmm... swwwwwaaaaaap!

foo_bar_foo · 06-17-2005, 09:04 PM

Code:

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>

extern int errno;

#define MAXMB (4<<10)
#define MB (1<<20)
#define PG (4<<10)

int main(argc,argv)
int argc;
char *argv[];
{
        char *m;
        int i,j;
        sleep(3);
        for(i=0;i<MAXMB;i++) {
                m=malloc(MB);
                printf("%d MB ...",i+1);
                if(errno || (m==NULL)) break;
                for(j=0;j<MB;j+=PG) m[j]='A';
                printf(" WooHoo\n");
        }
        printf("\n\nAllocated %d MB\n",i);
        exit(0);
}

in your face mem thingy

Code:

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            .'/,-Y"     "~-.
            l.Y             ^.
            /\               _\_      
           i            ___/"   "\
           |          /"   "\   o !
           l         ]     o !__./
            \ _  _    \.___./    "~\
             X \/ \            ___./
            ( \ ___.   _..--~~"   ~`-.
             ` Z,--   /               \
               \__.  (   /       ______)
                 \   l  /-----~~" /
                  Y   \          /
                  |    "x______.^
                  |           \      
                  j            Y