It might look very simple, but I haven’t found it anywhere already described. So I wanted to execute some task in Ansible playbook not always, with random decision. And the solution is simple as pie: tasks: - name: Random task debug: msg: 'This task runs randomly' when: 10 | random | bool So here we use Random Number Filter with bool filter. It will generate numbers from 0 to 10, and thanks to bool filter, the result will be true only if value will be equal to 1. According to this, this task will be executed once in 10 runs. You can change the number, to get more or less probability.

Another short note. I found the answer in the middle of issue on Grafana GitHub and decided to make a memo. So I wanted to show in ‘single stat’ panel number of alets. But when there is no alerts, my request returns no data , which is not so informative. And to solve this, you just need to add OR on() vector(0) to the end of your expression. It will return 0 if the metric expression does not return anything.

UPD: 1, 2 are still relevant for newer versions (0.15, 1.x) — In December 2020 a new version of Terraform was released — v0.14. Along with many new things there was released a pretty nice feature — Provider Dependency Lockfile. It will help you to verify provider binary authenticity and ensure that all environments will use not only the same provider version…

Summary of the ‘Efficient Go’ Book. Story from Thanos project inspired it. First Thanos compactor was implemented not very optimized and with increased usage in different companies issues started arising with memory overuse, OOM, etc. Solutions: Add an option to use less memory. …

Optimize what you need when you need. Don’t over optimize. Don’t guess. Measure everything and optimize based on data. Benchmarks go benchmark — built in with go, like tests. “go test -bench .” It’s possible to report allocations from benchmark context. Profiling Usually first you profile and then benchmark parts. But in…

Based on experience of reviewing PRs in metallb project. The less cognitive load, the less you spend energy. The simpler is solution, the less is load. Line of sight One line of happy path and next ident for exceptions. “Align to the left” There are different ways to achieve this. …

When you have a lot of code in the repository, like in monorepo case, it became very important to check in CI only things that changed in PR (pull request). Otherwise, CI will be slow and potentially broke on not your changes, which could ruin DevEx experience. If you’re using…

All modern code collaboration systems support CODEOWNERS. This is a file that stored in your repository and defines which team is responsible for which parts of code. It helps split responsibility between teams and together with review ensures that all changes are ok. This article is based on GitHub, but…

Ad-hoc fix for annoying Terraform “feature” in GH actions context — As I described in previous article, in terraform 0.15.4 HashiCorp added new thing which shows you what changed from previous apply. Sounds nice to see drift in infrastructure before apply, but in reality depending on providers/resources you’re using, it often ends in huge amount of output in terminal window, which…