They do mention it in the linked announcement, although not really highlighted, just as a quick mention:
> As a result, we’re very excited to share that in Ubuntu 25.10, some packages are available, on an opt-in basis, in their optimized form for the more modern x86-64-v3 architecture level
> Previous benchmarks we have run (where we rebuilt the entire archive for x86-64-v3 57) show that most packages show a slight (around 1%) performance improvement and some packages, mostly those that are somewhat numerical in nature, improve more than that.
ARM/RISC-V extensions may be another reason. If a wide-spread variant configuration exists, why not build for it? See:
- RISC-V's official extensions[1]
- ARM's JS-specific float-to-fixed[2]
> As a result, we’re very excited to share that in Ubuntu 25.10, some packages are available, on an opt-in basis, in their optimized form for the more modern x86-64-v3 architecture level
> Previous benchmarks we have run (where we rebuilt the entire archive for x86-64-v3 57) show that most packages show a slight (around 1%) performance improvement and some packages, mostly those that are somewhat numerical in nature, improve more than that.