Glossary

• abstraction ~ virtual - user-defined container which has properties (data) and methods (actions)
• artifacts - reminents of some process. Almost always related to build outputs, such as container images.
• cloud-native - a term used to describe tools or software that is designed to run in a virtualized environment of some kind.
• cluster - a group of something, usually compute related but not always.
• container registry - a place where container images are stored, for example GitHub Packages, AWS/Azure/GCP Container Registry, etc.
• Delta  - the HPC platform we use for running batch jobs and interactive GPU development
• DevOps - a loose set of practices focused on “shifting ops left”, e.g. giving developers more control and responsiblity over the deployment cycles of their code
• helm  - toolkit for packaging k8s manifests into reproducible templates, as opposed to Kustomize which embraces the philosophy of patching resources instead of templating them.
• Docker - a higher level set of tools designed to improve DX built on containerd (containerd images are what actually run on the cluster).
• GitOps - an extension of the DevOps philosophy that focuses on immutable, git-based deployments, where as much state as possible is store in version control.
• high performance compute (HPC) - a supercomputer in layman’s terms; hardware is often organized in such a way that favors performance over availability
• image - a compiled template, primarily for compute resources. A docker or containerd image might be used at the application level, but higher level images exist such as OS images.
• JetStream2 (JS2)  - while not exactly HPC, functions similar to it with a focus on hosting long-running, less compute intensive workloads
• Kubernetes (k8s) - open source container orchestration tool created by Google. Created via OpenStack Magnum, or in the Horizon UI  under “Container Infra”
• object storage - a system component primarily used for storing user-uploaded or other files that do not require random access. Since all paths for an object within Swift are known (unlike a filesystem - it wouldn’t make sense to search for every GET request), files can be stored and indexed more efficiently.
• OpenStack  - open source cloud hosted on JS2 to provide developer access to underlying resources (compute, storage, networking, etc). Each of these areas are packaged into modules, some of which are not supported by JS2.
• Terraform (TF)  - declarative, domain-specific language for representing infrastructure as code (IaaC). The TF cli produces a tfstate file that TF treats as the single source of truth. If you were to modify a resource created by via TF in the Horizon UI, any future attempts to modify the TF files used to create that resource will fail until the state is reconciled or refreshed. The difference between the tfstate and the live state of the infra that it corresponds to is known as drift, and phenomenon which also occurs with k8s manifests.
• worker node - a VM dedicated to doing work. For reliability reasons, many systems such as k8s separate the worker nodes from scheduler nodes (aka the control plane), which handle pod placement based on current resource consumption and the requirements of the pod.
• volume ~ block storage - a reserved, contiguous block of memory, primarily used for boot volumes and other types of files that need to be accessed randomly and have stronger fault tolerance requirements.