Play with the userfaultfd(2) system call and download on demand using HTTP Range Requests with Golang by rbranco

Description

The userfaultfd(2) is a cool system call to handle page faults in user-space. This should allow me to list the contents of an ISO or similar archive without downloading the whole thing. The userfaultfd(2) part can also be done in theory with the PROT_NONE mprotect + SIGSEGV trick, for complete Unix portability, though reportedly being slower.

Goals

1. Create my own library for userfaultfd(2) in Golang.
2. Create my own library for HTTP Range Requests.
3. Complete portability with Unix.
4. Benchmarks.
5. Contribute some tests to LTP.

Resources

1. https://docs.kernel.org/admin-guide/mm/userfaultfd.html
2. https://github.com/loopholelabs/userfaultfd-go
3. https://github.com/DHowett/ranger
4. https://www.cons.org/cracauer/cracauer-userfaultfd.html

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go-git: unlocking SHA256-based repository cloning ahead of git v3 by pgomes

Description

The go-git library implements the git internals in pure Go, so that any Go application can handle not only Git repositories, but also lower-level primitives (e.g. packfiles, idxfiles, etc) without needing to shell out to the git binary.

The focus for this Hackweek is to fast track key improvements for the project ahead of the upstream release of Git V3, which may take place at some point next year.

Goals

• Add support for cloning SHA256 repositories.
• Decrease memory churn for very large repositories (e.g. Linux Kernel repository).
• Cut the first alpha version for go-git/v6.

Stretch goals

• Review and update the official documentation.
• Optimise use of go-git in Fleet.
• Create RFC/example for go-git plugins to improve extensibility.
• Investigate performance bottlenecks for Blame and Status.

Resources

• https://github.com/go-git/go-git/
• https://go-git.github.io/docs/

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Create a go module to wrap happy-compta.fr by cbosdonnat

Description

https://happy-compta.fr is a tool for french work councils simple book keeping. While it does the job, it has no API to work with and it is tedious to enter loads of operations.

Goals

Write a go client module to be used as an API to programmatically manipulate the tool.

Writing an example tool to load data from a CSV file would be good too.

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terraform-provider-feilong by e_bischoff

Project Description

People need to test operating systems and applications on s390 platform.

Installation from scratch solutions include:

• just deploy and provision manually (with the help of ftpboot script, if you are at SUSE)
• use s3270 terminal emulation (used by openQA people?)
• use LXC from IBM to start CP commands and analyze the results
• use zPXE to do some PXE-alike booting (used by the orthos team?)
• use tessia to install from scratch using autoyast
• use libvirt for s390 to do some nested virtualization on some already deployed z/VM system
• directly install a Linux kernel on a LPAR and use kvm + libvirt from there

Deployment from image solutions include:

• use ICIC web interface (openstack in disguise, contributed by IBM)
• use ICIC from the openstack terraform provider (used by Rancher QA)
• use zvm_ansible to control SMAPI
• connect directly to SMAPI low-level socket interface

IBM Cloud Infrastructure Center (ICIC) harnesses the Feilong API, but you can use Feilong without installing ICIC, provided you set up a "z/VM cloud connector" into one of your VMs following this schema.

What about writing a terraform Feilong provider, just like we have the terraform libvirt provider? That would allow to transparently call Feilong from your main.tf files to deploy and destroy resources on your system/z.

Other Feilong-based solutions include:

• make libvirt Feilong-aware
• simply call Feilong from shell scripts with curl
• use zvmconnector client python library from Feilong
• use zthin part of Feilong to directly command SMAPI.

Goal for Hackweek 23

My final goal is to be able to easily deploy and provision VMs automatically on a z/VM system, in a way that people might enjoy even outside of SUSE.

My technical preference is to write a terraform provider plugin, as it is the approach that involves the least software components for our deployments, while remaining clean, and compatible with our existing development infrastructure.

Goals for Hackweek 24

Feilong provider works and is used internally by SUSE Manager team. Let's push it forward!

Let's add support for fiberchannel disks and multipath.

Possible goals for Hackweek 25

Modernization, maturity, and maintenance.

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Rewrite Distrobox in go (POC) by fabriziosestito

Description

Rewriting Distrobox in Go.

Main benefits:

• Easier to maintain and to test
• Adapter pattern for different container backends (LXC, systemd-nspawn, etc.)

Goals

• Build a minimal starting point with core commands
• Keep the CLI interface compatible: existing users shouldn't notice any difference
• Use a clean Go architecture with adapters for different container backends
• Keep dependencies minimal and binary size small
• Benchmark against the original shell script

Resources

• Upstream project: https://github.com/89luca89/distrobox/
• Distrobox site: https://distrobox.it/
• ArchWiki: https://wiki.archlinux.org/title/Distrobox

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