Ubuntu 18.04 LTS could be the first release to ship without a 32-bit version if suggestions on an Ubuntu mailing list are acted upon. Dmitri John Ledkov, who suggested dropping i386 support, points out that building i386 (32-bit) images is not free, but “comes at the cost of utilising our build farm, QA and validation time". He questioned whether Canonical could “effectively provide security support on i386”, and drew up a plan on how 32-bit components could be phased out over the course of the next two years.
By 2018, it will have been over two years since several third-party independent software vendors (ISVs) stopped supporting software on 32-bit systems. Some of the software Ledkov cited include Google Chrome, ZFS, and Docker. Aside from ISVs dropping support for 32-bit systems, he also points out all the work that goes into releasing 32-bit images and the extra mirror space and bandwidth they use as reasons to drop the architecture.
The example draft plan that Ledkov drew out works as follows:
Ubuntu 16.10, 17.04, 17.10:
- Continue to provide the i386 (32-bit) port to run legacy applications on amd64 (64-bit).
- Continue to build the i386 d-i/netboot installer.
- Continue to build the i386 kernel.
- Continue to build the i386 cloud-images.
- Stop producing the i386 ubuntu-desktop.iso.
- Stop producing the i386 ubuntu-server.iso.
Ubuntu 18.04 LTS:
- Continue to provide the i386 port to run legacy applications on amd64.
- Stop producing the i386 d-i/netboot installer.
- Stop producing the i386 kernel.
- Stop producing the i386 cloud-images.
- Stop producing the i386 ubuntu-desktop.iso.
- Stop producing the i386 ubuntu-server.iso.
Ubuntu 18.10+:
- Stop providing the i386 port.
- Run legacy i386 only applications in snaps/containers/virtual machines.
It"s not clear just yet what will happen about support for 32-bit Ubuntu but Canonical has released a survey per a request from Ledkov to gauge users opinions on when i386 support should end. If Ubuntu drops i386 support, April 2021 would be the “sunset” for i386 as the host/base OS architecture, and April 2023 would be the last time legacy i386 applications would receive security updates.
Source: Ubuntu Mailing List via Phoronix