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From: Denis Vlasenko <vda@ilport.com.ua>
To: "John Pearson" <john@illhostit.com>,
       "Erik Mouw" <erik@harddisk-recovery.com>, "Ashley" <ashleyz@alchip.com>
Subject: Re: Kernel cached memory
Date: Sat, 23 Jul 2005 15:31:20 +0300
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On Saturday 23 July 2005 00:43, John Pearson wrote:
> Wouldn't having (practically) all your memory used for cache slow down
> starting a new program? First it would have to free up that space, and then
> put stuff in that space, taking potentially twice as long. I think there
> should be a system call for freeing cached memory, for those that do want to
> do it.

I think this one is good enough:

#include <stdlib.h>

int main() {
    void *p;
    unsigned size = 1<<20;
    unsigned long total=0;
    while(size) {
        p = malloc(size);
        if(!p) size>>=1;
        else {
            memset(p, 0x77, size);
            total+=size;
            printf("Allocated %9u bytes, %12lu total\n",size,total);
        }
    }
    return 0;
}

You may want to adapt it so that it takes an argument now many megabytes
to eat before it dies.
--
vda