> It was supposed to be much faster than "bloated ubuntu", but I suspect now it was mostly placebo
Gentoo predates Ubuntu by several years. I remember reading some "gentoo ricer" threads bike-shedding over ultimately inconsequential optimization flags. But don't underestimate the simple benefit of `-march` and similar. At a time when binary distributions were pushing x86 binaries which ran on i386, compiling for a newer architecture could give a substantial increase in registers available, instructions available, and instruction scheduling quality. In aggregate, this definitely can improve performance.
Since then, I believe Debian moved to an i686 base which narrows the gap.
Gentoo predates Ubuntu by several years. I remember reading some "gentoo ricer" threads bike-shedding over ultimately inconsequential optimization flags. But don't underestimate the simple benefit of `-march` and similar. At a time when binary distributions were pushing x86 binaries which ran on i386, compiling for a newer architecture could give a substantial increase in registers available, instructions available, and instruction scheduling quality. In aggregate, this definitely can improve performance.
Since then, I believe Debian moved to an i686 base which narrows the gap.