Trying Out The Ubuntu "-O3" Optimized Build For Greater Performance

[phoronix]

Phoronix: Trying Out The Ubuntu "-O3" Optimized Build For Greater Performance

Canonical engineers on Friday announced they are evaluating "-O3" compiler optimized package builds for Ubuntu Linux. As part of this evaluation of using GCC's -O3 compiler optimization level rather than -O2 when compiling Ubuntu packages, experimental Ubuntu desktop and server ISOs are available for testing with this change. Excitingly I ran some initial benchmarks over the weekend in looking at the performance difference.

https://www.phoronix.com/review/ubuntu-o3-experiment

[royce]

Fuck-all difference really. Except a workload here and there there's really no difference. Still, a smidge faster. What's the downside of going down that route?

[AHSauge]

Fuck-all difference really. Except a workload here and there there's really no difference. Still, a smidge faster. What's the downside of going down that route?

Bigger binaries presumably

[tabicat]

What's the downside of going down that route?

Exposure to more compiler bugs.

[rene]

told you so ¯\_(ツ)_/¯

[varikonniemi]

Perfect evidence against this optimization masturbation, many tests even had severe performance regression!

There are better things to spend time on than trying to outsmart the author of the code you are compiling.

[Errinwright]

It looks decent to me to be frank

[NomadDemon]

how about binary size?

[sophisticles]

If a program is properly coded then there should be little to no benefit form compiler optimizations.

If there is a program that shows large improvements that means the developer is either lazy or incompetent.

I also wonder about potentially negative consequences of more aggressive compiler settings, such as incorrect output or stability issues due to the introduction of unexpected behavior.

[V1tol]

I thought Ubuntu wanted to provide x86-64-v3 builds and not just -O3? Really -O3 is not even worth testing on modern processors with code targeting Athlon 64 from 2003.