Re: CONFIG_TINY

Rob Landley
2002-11-04T07:08:22Z

On Friday 01 November 2002 14:15, Tom Rini wrote:

> > Sure, and unrolling loops can cause cache misses and be slower than that
> > jmp back in a loop. The point is this is a string, the people who think
> > they're able to hand diddle the options can change it. And more to the
> > point anyone who can't find a string in a makefile shouldn't be second
> > guessing the compiler anyway.
>
> Yes, so why can't those who still need a few more kB after trying some
> of the other options go and find '-O2' and replace it with '-Os' ?

Because the point of CONFIG_TINY is to make the kernel smaller and this is
something that makes the kernel smaller? (In fact telling the compiler
"optimize for size" is one of the most OBVIOUS things to do?)

I've used -Os. I've compiled dozens and dozens of packages with -Os. It has
always saved at least a few bytes, I have yet to see it make something
larger. And in the benchmarks I've done, the smaller code actually runs
slightly faster. More of it fits in cache, you know.

Rob

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