Inject GOMEMLIMIT into guest VM to prevent Go tool OOM kills#124
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Inject GOMEMLIMIT into guest VM to prevent Go tool OOM kills#124
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Go tools spawned by agents (e.g. golangci-lint) do not auto-detect VM memory limits because the guest has no cgroup boundary. Without GOMEMLIMIT the GC grows the heap unbounded until the OOM killer fires, which freezes the terminal session. Add GoMemLimitPercent to the agent definition (mirroring the existing NodeHeapPercent pattern) and set it to 70% for all built-in agents. With a 10 GB VM this yields GOMEMLIMIT=7168MiB, giving the Go GC a soft ceiling while leaving headroom for Node.js and system overhead. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
jhrozek
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Apr 17, 2026
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it would be cool to be able to set env vars like this through sub-agents. But great, this is probably why I've been seeing occasionaly OOMs as well.
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Summary
golangci-lint) don't auto-detect VM memory limits — the guest runs its own kernel with no cgroup boundary, so the Go GC has no soft ceiling and grows unbounded until the OOM killer firesGoMemLimitPercentto the agent definition (same pattern as the existingNodeHeapPercent/NODE_OPTIONScap) and injectsGOMEMLIMITinto/etc/sandbox-envGOMEMLIMIT=7168MiB, leaving headroom for Node.js and system overheadContext
Observed
golangci-lint(3.6 GB RSS) getting OOM-killed inside a 10 GB VM, which left the SSH session frozen. The kernel'soom_score_adjfired because no Go GC soft limit was in place.Test plan
task fmt— cleantask lint— 0 issuestask test— all passing🤖 Generated with Claude Code