fix(step-ca): prevent PID exhaustion from zombie health check processes#120
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rdemeritt wants to merge 1 commit into
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fix(step-ca): prevent PID exhaustion from zombie health check processes#120rdemeritt wants to merge 1 commit into
rdemeritt wants to merge 1 commit into
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Add init: true so tini reaps zombie children spawned by Docker's health check mechanism. Switch healthcheck from CMD-SHELL to CMD (exec) form to eliminate the intermediate /bin/sh child, halving the fork rate. Without these fixes, step-ca accumulates ~14k zombie PIDs over ~25 hours until fork() returns EAGAIN and the container goes permanently unhealthy.
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Summary
CMD-SHELL, which forks/bin/sh → wget. Since step-ca Go binary is PID 1 and doesn't reap children, each health check cycle leaves zombie processes. Eventuallyfork()returnsEAGAINand the container goes permanently unhealthy.init: true): Docker injectstinias PID 1, which properly reaps all zombie children from health check forks — the permanent fix.CMD-SHELLtoCMDexec form, eliminating the intermediate/bin/shprocess and halving the fork rate per health check cycle.Option A (container restart) was already applied directly on macbeth to restore health immediately.
Test plan
./scripts/start.sh -d --buildcopper-rabbit-step-ca-1shows(healthy)indocker ps