CentOS Hyperscale SIG Quarterly Report for 2021Q2

This report covers work that happened between April 2nd and June 30th. For previous work, see the 2021Q1 report.

Purpose

The Hyperscale SIG focuses on enabling CentOS Stream deployment on large-scale infrastructures and facilitating collaboration on packages and tooling.

Membership update

Since the last update, the SIG gained one new member (Jim Heald).

We welcome anybody that’s interested and willing to do work within the scope of the SIG to join and contribute. See the membership section on the wiki for the current members list and how to join.

Releases and Packages

Unless otherwise specified, packages are available in our main repository, which can be enabled with dnf install centos-hyperscale-release. Please report any issues with these packages on our package-bugs tracker.

systemd

Our most recent backport of systemd is version 248 based on the Fedora packaging. This release includes a host of new features including system extension images and systemd-oomd.

systemd-oomd was declared stable in systemd 248 and was adopted in Fedora 34 as the default userspace out-of-memory killer. It monitors memory pressure thresholds and kills processes at the cgroup level. The systemd-oomd-defaults package, which provides the policy used by Fedora, is also backported to our repository.

In addition to release builds, we’re also producing daily systemd builds via the CentOS CI infrastructure. These builds track the upstream git head and can be useful to test the latest changes and features, while also helping spot potential build issues ahead of time.

Finally, we’ve published a staging tree and our build and release scripts to make future development work more accessible to contributors.

LLVM

A non-modular version of the LLVM 12 compiler suite is now shipped in Hyperscale. This is meant as a stopgap, and will be removed once a modular version of LLVM 12 becomes available in CentOS Stream proper.

Because this is a set of non-modular packages overriding a module, it is being delivered in a new repository to be used as a modularity hotfix repository. This repository can be enabled with dnf install centos-release-hyperscale-hotfixes.

DNF/RPM stack with CoW support

An updated packaging stack (rpm, dnf, libdnf, librepo) is now available in the experimental repository. These packages include several improvements and bugfixes to support the ongoing Copy-on-Write work. The experimental repo can be enabled with dnf install centos-release-hyperscale-experimental.

Kernel

We have a 5.12.4 release of the Linux kernel currently in our experimental repository. This kernel has btrfs and Kernel Live Patching enabled. We’ve taken steps to ensure our nascent kernel process is compatible with kernel-ark to enable smoother updates and CI.

kpatch

We ship a modified version of kpatch 0.9.3 that includes a few additional backports from upstream. Our packaging of kpatch also includes the kpatch-build tool, which can be used to convert kernel patches to be then applied onto a system that supports Kernel Live Patching.

Storage stack and Installer

We have rebuilt a number of components to restore Btrfs support:

• libblockdev
• python-blivet
• udisks2

and built a backport of btrfs-progs. Additionally, we have branched and built the Anaconda installer based on version 33.16.5.2 with support for Btrfs restored and a number of backports from Anaconda 34 to enable building spins based on Hyperscale content. Our version of the installer also includes the anaconda-live package for supporting installation from live media.

Container image

A minimal container image based on the Hyperscale SIG repos and packages is now available on Quay.io and can be used via Docker or Podman:

podman run -a stdin,stdout,stderr -t quay.io/centoshyperscale/centos:stream8

This container image is built from scratch, and in the future we plan to leverage the CentOS CI infrastructure to automate the build process.

Live media

An experimental CentOS Hyperscale Workstation Live DVD image is now available. This image is currently based on the GNOME desktop shipped in CentOS Stream 8 and is combined with the packages we’ve shipped in the Hyperscale SIG, notably the live installer and storage stack software. A KDE Plasma variant is forthcoming.

The live media is built using livecd-creator from the LiveCD Tools provided by the livecd-tools package in EPEL. We published the kickstarts as well.

Issues with this image can be reported on our spin-bugs tracker.

libvirt

We ship an updated backport of libvirt 7.1.0. Due to CBS being unable to build modules, this is shipped as a non-modular package in the hotfixes repository mentioned earlier.

mock-centos-sig-configs

We have announced the availability of a mock-centos-sig-configs project to hold mock configurations for CentOS SIGs. The goal is to make it easier to build packages against a given SIG when doing local testing and development. The project currently contains configs for the Hyperscale SIG, but other SIGs are welcome to contribute their configs as well.

Other packages

There are several other backports we’re shipping within the SIG:

• dracut 0.55, which has undergone some significant code cleanup and testing
• emacs 27.2, which is required by the popular configuration framework Doom Emacs
• less 581.2, which is required by recent systemd versions.
• hdparm 9.62, which includes an upstream fix for --dco-identify
• rasdaemon 0.6.7, a hardware error logging tool

We’re also made available a modified version of util-linux 2.32.1 that includes support for setpriv --reset-env and for the CAP_CHECKPOINT_RESTORE capability.

Health and Activity

The SIG continues to maintain a healthy development pace.

Meetings

The SIG holds regular bi-weekly meetings on Wednesdays at 16:00 UTC. Meetings are logged and the minutes for past meetings are available.

The SIG uses the #centos-hyperscale IRC channel for ad-hoc communication and work coordination, and the centos-devel mailing list for async discussions and announcements. As of April, the SIG also holds open monthly video conference sessions to promote collaboration and social interaction.

Conference talks

An update on the SIG was presented at CentOS Dojo, May 2021 (recording). SIG activities were also covered as part of LISA21 (recording), and another talk has also been submitted for DevConf.us 2021.

As of June, Neal Gompa has been streaming ad-hoc SIG-related work sessions on his Twitch channel. To this end, we have created a dedicated CentOSHyperscale channel that we plan to use going forward to promote and collate SIG related content.

Planned work

The SIG tracks pending work as issues on our Pagure repository. Notable projects currently in flight include:

• productionize the Live media image
• integrate btrfs transactional updates as an optional feature
• setup a continuous build pipeline for the container image on the CentOS CI infrastructure
• integrate our kernel development process with kernel-ark
• build a set of Hyperscale-enabled Cloud images
• enable fsverity support in rpm

Issues for the Board

We have no issues to bring to the board’s attention at this time.