RFR: 8210416: [linux] Poor StrictMath performance due to non-optimized compilation

Severin Gehwolf sgehwolf at redhat.com
Mon Sep 10 12:43:24 UTC 2018

Hi Andrew,

On Mon, 2018-09-10 at 10:05 +0100, Andrew Haley wrote:
> On 09/05/2018 02:12 PM, Severin Gehwolf wrote:
> > Is there a good
> > reason to not use -O3 -ffp-contract=off everywhere?
> Is there a good reason to use -O3 rather than -O2? -O3 can bloat the
> code which can increase cache pressure, which is not always noticeable
> in benchmarks but hurts real-world programs. Unless benchmarks are
> significantly better at -O3, -O2 is a good default choice.

As I'm not seeing significant difference between -O2 and -O3, I've
switched to LOW (corresponding to -O2) as default. See:


More information about the core-libs-dev mailing list