Re: Why not build kernel with -O3

From: Richard Weinberger
Date: Wed Apr 08 2015 - 08:19:09 EST

On Wed, Apr 8, 2015 at 3:00 AM, Pengfei Yuan <0xcoolypf@xxxxxxxxx> wrote:
> Could you please provide some examples that I can investigate?
> Thanks!

It would be awesome if you could find out which gcc optimizations
cause the speed up.
"gcc -c -Q -O3 --help=optimizers" will help you.

Please also double check your results.
You need do to multiple runs, etc...
Especially the redis speed up looks odd. Does redis really spend that much time
in the kernel?

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at