feat(shield): set GOMAXPROCS/GOMEMLIMIT for Go workloads on Windows - #2660
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francesco-furlan wants to merge 1 commit into
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feat(shield): set GOMAXPROCS/GOMEMLIMIT for Go workloads on Windows#2660francesco-furlan wants to merge 1 commit into
francesco-furlan wants to merge 1 commit into
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Windows containers have no cgroups, so the Go runtime cannot auto-detect the container's CPU/memory limits and falls back to whole-node CPU count with no memory ceiling. Set GOMAXPROCS/GOMEMLIMIT explicitly via the downward API (resourceFieldRef) so they track whatever the chart renders. - New common.go_runtime.envs helper emits each var only when its limit is set - host-shield-windows DaemonSet: always tuned (always Windows) - cluster-shield Deployment: tuned only when pinned to Windows nodes, detected via the effective nodeSelector (kubernetes.io/os: windows) - Emitted before the user-env include so users can still override - Linux host-shield left unchanged (Go auto-detects cgroup limits there)
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What
Sets
GOMAXPROCS/GOMEMLIMITexplicitly for Shield's Go workloads on Windows, derived from each container's own resource limits via the downward API (resourceFieldRef).Why
Modern Go reads cgroup CPU/memory limits automatically on Linux. Windows containers have no cgroups, so the runtime falls back to whole-node CPU count and no memory ceiling — causing scheduler contention and OOM risk under tight limits. We pin the runtime to whatever the chart renders, only where Go can't auto-detect (Windows).
Changes
templates/common/_go_runtime.tpl(new) —common.go_runtime.envshelper. Emits each env var only when its matching limit is set (limits.cpu→GOMAXPROCS,limits.memory→GOMEMLIMITwithdivisor: "1").templates/host/daemonset-windows.yaml— always tuned (always Windows).templates/cluster/deployment.yaml— tuned only when pinned to Windows nodes.templates/cluster/_helpers.tpl— newcluster.scheduled_on_windowsdetector (checks effective nodeSelector forkubernetes.io/os: windows).host-shieldDaemonSet left unchanged (Go auto-detects there).Chart.yamlbumped1.43.2→1.44.0.Notes
Verification
helm template: Windows DaemonSet always tuned; cluster-shield tuned only when Windows-pinned; both gated on limits; Linux host DaemonSet untouched.helm unittest: 37 suites / 560 tests pass.🤖 Generated with Claude Code