fix: add zombie process reaper for PID 1 containers#153
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alecthomas merged 1 commit intomainfrom Feb 24, 2026
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When cachewd runs as PID 1 in a container, orphaned grandchild processes (e.g. git-upload-pack spawned by git http-backend) get reparented to it. Go's cgi.Handler properly reaps the direct child but has no mechanism to reap these grandchildren, so they accumulate as zombies. Add a background reaper that periodically calls waitpid(-1, WNOHANG) to collect any zombie children. It only activates when running as PID 1. Fixes #151
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When cachewd runs as PID 1 in a container, orphaned grandchild processes (e.g.
git-upload-packspawned bygit http-backend) get reparented to it. Go'scgi.Handlerproperly reaps the direct child but has no mechanism to reap these grandchildren, so they accumulate as zombies.Adds a background reaper that periodically calls
waitpid(-1, WNOHANG)to collect any zombie children. It only activates when running as PID 1.Fixes #151