Ubuntu prides itself on being among the most compatible Linux distributions. Compatibility is often a conscious trade-off against bleeding-edge performance. In Ubuntu 25.10, we have added support for packages that target specific silicon variants, meaning you can have your cake and eat it too!
Back in 2023 I wrote an article talking about the history of the amd64 / x86-64 architecture and described the “levels” x86-64-v2 , -v3 , and -v4 (often referred to as amd64v3 , amd64v4 , etc.). Since then, we’ve been working on a means to better exploit modern processors without compromising support for older hardware.
To do this, we have added the concept of an “architecture variant.” By making changes to dpkg , apt and Launchpad, we are able to build multiple versions of a package, each for a different level of the x86-64 architecture, meaning we can have packages that specifically target x86-64-v3 , for example.
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.
What’s been done?
For 25.10 we were mostly focused on building the required infrastructure and have not yet rebuilt every package for the x84-64-v3 / amd64v3 architecture. Most packages in the main component have been rebuilt (around 2000 source packages). It is worth noting that these packages have not yet received the usual level of testing that most packages in Ubuntu receive. So while we expect them to work, early adopters might find some bugs.
For the upcoming 26.04 LTS release, we will rebuild amd64v3 -enabled versions of all packages and test them in the same rigorous way as we test every other Ubuntu package.
Previous benchmarks we have run (where we rebuilt the entire archive for x86-64-v3) 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.
Try it out
The vast majority of cloud instance types and machines manufactured within the last ten years will support x86-64-v3 , and you can check for support on a machine like so:
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