Re: Optimization levels when compiling PostgreSQL...

Sean Chittenden wrote:
> > > > The size difference between -O and -O3 is only 200K or so... does
> > > > anyone think that it'd be safe to head to -O6 on a wide scale?
> > >
> > > Dunno. I'm not aware of any bits of the code that are unportable enough
> > > to break with max optimization of any correct compiler. But you might
> > > find such a bug. Or a bug in your compiler. Are you feeling lucky
> > > today?
> > >
> > > My feeling is that gcc -O2 is quite well tested with the PG code.
> > > I don't have any equivalent confidence in -O6. Give it a shot for
> > > beta-testing, for sure, but I'm iffy about calling that a
> > > production-grade database release...
> >
> > And of course the big question is whether you will see any performance
> > improvement with -O6 vs. -O2. My guess is no.
>
> Agreed, however some of the loop-unrolling might prove to have some
> optimization, but we'll see. I'd like to think that there's some
> actual value in -O6 beyond the geek appeal of being able to say it's
> been compiled with all the optimizations possible. ::shrug::

And you think the answer is ... I think we all know what the answer is.
:-)

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