RE: Large File support and blocks.

From: Linda Walsh (law@sgi.com)
Date: Thu Aug 31 2000 - 16:57:58 EST


And the below is what percentage of time doing disk i/o?

> Just put this in a loop and time it. Change SIZE to long long, and do
> it again! It doesn't scale well. The long long code is nearly 10 times
> slower! You can do `gcc -S -o xxx name.c` and see why.
>
>
> #define SIZE long
>
> SIZE *foo()
> {
> SIZE one;
> SIZE two;
> static SIZE answer[8];
>
> one = 1;
> two = 2;
> answer[0] = one - two;
> answer[1] = two - one;
> answer[2] = one + two;
> answer[3] = two + one;
> answer[4] = two / one;
> answer[5] = one / two;
> answer[6] = one * two;
> answer[7] = two * one;
> return answer;
> }
>
>
> Long long things, even it they work well, are not very nice on 32 bit
> machines. For the time being, I'd advise increasing cluster size rather
> than using 64 bit values.
>
> In a few years, even Intel machines will be 64 bits. Int will still be
> long, but it will be 64 bits. ---and they will autoscale for backwards
> compatibility (one new instruction, used once, for oprand size).
>
> Cheers,
> Dick Johnson
>
> Penguin : Linux version 2.2.15 on an i686 machine (797.90 BogoMips).
>
> "Memory is like gasoline. You use it up when you are running. Of
> course you get it all back when you reboot..."; Actual explanation
> obtained from the Micro$oft help desk.
>
>
>
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