Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!murtoa.cs.mu.oz.au!ditmela!yarra!melba!gnb From: gnb@melba.bby.oz (Gregory N. Bond) Newsgroups: comp.unix.wizards Subject: Re: when does kill -9 pid not work? Message-ID: <149@melba.oz> Date: 17 Aug 89 01:19:44 GMT References: <20532@adm.BRL.MIL> Organization: Burdett, Buckeridge & Young Ltd, Melbourne Lines: 22 Reply-To: One source of non-interruptable sleeps in live processes is kernel-based network services. (My experience is with SunOS 3.5 kernels, but I suspect most NFS implemenations would have the same problems.) I have had a number of experiences with processes hanging when things like lockd or statd or portmap are dead on a machine on the network. These are things used by the kernel alorithms, so are < PZERO priority. This morning, suntools on one workstation was frozen because one process was trying to lock a file, and the local statd was dead. kill -9 wouldn't kill the process. When the statd was restarted (a hairy experience, too!) the process went away and the accumulated input events were processed by the window system. These are an indication that the paradigm for NFS in huge kernels is a bit strained. Perhaps a mach-like messages-with-kernel-processes paradigm could avoid this? Greg.-- Gregory Bond, Burdett Buckeridge & Young Ltd, Melbourne, Australia Internet: gnb@melba.bby.oz.au non-MX: gnb%melba.bby.oz@uunet.uu.net Uucp: {uunet,pyramid,ubc-cs,ukc,mcvax,prlb2,nttlab...}!munnari!melba.bby.oz!gnb