fix: reap zombie worker processes in containerized environments#2184
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MetaAlms wants to merge 1 commit into
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fix: reap zombie worker processes in containerized environments#2184MetaAlms wants to merge 1 commit into
MetaAlms wants to merge 1 commit into
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TEN workers are spawned via tman, which forks a [main] subprocess. When tman receives SIGKILL during stop(), it has no chance to wait() for [main]. [main] becomes an orphan and accumulates as zombie. Register a SIGCHLD handler to automatically reap all orphaned child processes via waitpid(-1, WNOHANG).
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Problem
In containerized environments without a proper init system (PID 1), TEN Agent Server spawns [main] worker processes via
tman run start. When the worker is stopped,tmanexits without callingwait()on its child [main], leaving zombie processes that accumulate over time.Root Cause
The server starts
tmanwithSetpgid: true, then kills the process group viasyscall.Kill(-pid, SIGKILL).tmanis terminated before it can reap its child [main], so the kernel re-parents the child to PID 1. In a container, PID 1 is the Go server itself, which does not callwaitpid()on child processes outside its owncmd.Wait()goroutine.Fix
Register a
SIGCHLDhandler inworker_linux.gothat callswaitpid(-1, WNOHANG)in a loop to reap any zombie children re-parented to PID 1.Verification
go build ./...passesRelated
This is a standard Linux pattern for init-less containers. The handler is placed in
worker_linux.go(linux || darwinbuild tag) since it relies onsyscall.SIGCHLDandsyscall.Wait4.