Hi,
You can't kill that which is already dead.
You'll have to investigate the parent process, because the defuncts will stay until the parent reads their return code.
Open a case for whatever software owns the parent process.
You may have some luck by sending a SIGCHLD to the parent process (assuming it isn't completely broken)
There is a special case for init (PID 1): If you find defuncts with a PPID of 1, it usually means that init didn't finish it's initial processing (some inittab entry with "wait" didn't finish).
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José Pina Coelho
IT Specialist at Kyndryl
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