GCC Benchmarks At Varying Optimization Levels With Core i9 10900K Show An Unexpected Surprise

With the Intel Core i9 10900K "Comet Lake" processor here are some fresh GCC compiler benchmarks when looking at the performance of GCC 8.4 versus 9.3 versus a 10.2 snapshot while testing with optimization flags of -O2, -O3 -march=native, and -O3 -march=native -flto.

On Ubuntu 20.04 with the Linux 5.8 kernel the compilers GCC 8.4.0, GCC 9.3.0, and a GCC 10.2 snapshot were built from source while using the same build arguments across all tested builds and using the same compiler (Ubuntu 20.04 default compiler) for building these different GCC compiler releases. Various C/C++ benchmarks were carried out with each GCC release while setting the CFLAGS/CXXFLAGS to "-O2", "-O3 -march=native", and "-O3 -march=native -flto" for a mix of common optimization levels.

Via the Phoronix Test Suite dozens of different benchmarks were carried out for looking at the compiler performance on the current Core i9 10900K that still makes use of the Skylake era target.