From Fedora Project Wiki


tzdata-minimal

Summary

Split the tzdata package into two parts - tzdata and tzdata-minimal. tzdata will require tzdata-minimal. tzdata-minimal provides the minimal files needed to support UTC on containers.

Owner

  • Name: Patsy Griffin (Franklin)
  • Email: patsy@redhat.com


Current status


  • Targeted release: Fedora Linux 35
  • Last updated: 2021-07-14
  • FESCo issue: #2647
  • Tracker bug: <will be assigned by the Wrangler>
  • Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

This is the first step towards providing support for a minimal, UTC only, version of tzdata for containers. The tzdata-minimal package will be a stand-alone, UTC only, subset of tzdata. The tzdata package will require tzdata-minimal.

With this framework in place, other packages can develop code to detect a minimal tzdata installation. These packages will also need to provide appropriate messages when users request timezone information not available when only tzdata-minimal is installed.

Feedback

We have had requests for this functionality in order to support minimal container installations. Currently some container kickstart installations already ad hoc remove most of the timezone information provided by tzdata, leaving only UTC support available. This change provides a formal method of providing this support.

Both the glibc and python teams are aware of this proposed change. This change does not currently require changes in their code. The goal is for those packages that currently require tzdata as part of their build or install, move towards recommending tzdata instead.

Benefit to Fedora

This change will reduce the size of base container installations.

Scope

  • Proposal owners: Implement the proposal.
  • Other developers: Developers need to ensure that their packages continue to build and install with the new split tzdata/tzdata-minimal package changes.
  • Release engineering: No coordination required with Release Engineering.
  • Policies and guidelines: The policies and guidelines do not need to be updated.
  • Trademark approval: N/A (not needed for this Change)
  • Alignment with Objectives: N/A

Upgrade/compatibility impact

The only visible change will be a new package tzdata-minimal required by tzdata.


How To Test

Run a dnf upgrade of tzdata and observe that tzdata-minimal is now also installed as a dependency.


User Experience

Users will see that new updates to tzdata include a new package dependency on tzdata-minimal.

Dependencies

This change does not require or depend on changes to other packages. However, we hope that dependent packages will work towards recommending tzdata for builds and installs rather than requiring it.


Contingency Plan

  • Contingency mechanism: If we are unable to complete this feature by the final development freeze, we will revert to the shipped configuration.
  • Contingency deadline: 100% Code complete deadline
  • Blocks release? No

Documentation

No documentation changes are needed at this time.


Release Notes

The tzdata package is now divided into a UTC only package, tzdata-minimal, and tzdata.