Zot chart

This chart installs the Zot registry. It is based on the official upstream chart.

Contributing

Please note: this repo is managed using the git-subtree module, all PRs have to be merged with merge commits, not squashes!

Memory management recommendations

Generic requests and limits with VPA

This is the standard approach. VPA is enabled by default with room to increase Zot deployment CPU and memory limits.

Fixed memory usage with Go GC configuration

In this use case, we recommend disabling the VPA and set a fixed memory request and limit (same value) for the Zot deployment. Alongside that, configure the Go Garbage Collector with .env Helm values.

We recommend setting GOMEMLIMIT to about 80% of the pod memory limits. You should not set GOGC higher than 100.

See: https://tip.golang.org/doc/gc-guide

# With the fix memory usage, we recommend not using a VPA in this scenario as the GOMEMLIMIT will hard limit the memory usage
giantswarm:
  verticalPodAutoscaler:
    enabled: false

# Leave some room for the CPU usage as the GC will require it to clean it
resources:
  requests:
    cpu: 300m
    # Fixed request
    memory: 1024Mi
  limits:
    cpu: 500m
    # Fixed limit
    memory: 1024Mi

# Configure the Go Garbage Collector via environment variables
env:
  - name: "GOGC"
    # Keep it around 50, cannot be increased beyond 100
    value: "50"
  - name: "GOMEMLIMIT"
    # About 80% of the fixed memory limit
    value: "800MiB"

Setting a high enough priority class can also help keeping the deployment a little more stable.

Notes on extension memory usage

In our experience, enabling the Zot ui and search (needed for ui extension) significantly increases the memory requirements for Zot.