[OE-core] Default value for FULL_OPTIMIZATION

Phil Blundell pb at pbcl.net
Wed Feb 3 21:08:28 UTC 2016


On Wed, 2016-02-03 at 12:59 -0800, Khem Raj wrote:
> in systems of  this age it should be yet.

Sorry, I didn't really understand that comment.

For what it's worth, as a very quick and fairly unscientific comparison,
I did "time make -j4" in a glibc tree and got:

real	1m38.812s
user	4m6.420s
sys	0m23.148s

and then I cleaned the tree and did "time make -j4 CFLAGS='-O2 -g
-pipe'" and got:

real	1m37.299s
user	4m21.420s
sys	0m27.304s

I'm not sure these results are statistically significant but on this
very limited evidence it certainly doesn't look like -pipe is providing
any transformational benefits.  The real time has gone down a tiny bit,
which suggests that -pipe is giving some extra parallelism, but the
system and user time have both actually gone up in the second case. 

p.





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