From owner-freebsd-hackers@freebsd.org Thu Nov 28 11:08:56 2019 Return-Path: Delivered-To: freebsd-hackers@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 40A451CDA28 for ; Thu, 28 Nov 2019 11:08:56 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [IPv6:2a01:4f8:c2c:26d8::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 47Nvyv2kRpz4RHt for ; Thu, 28 Nov 2019 11:08:54 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (eg.sd.rdtc.ru [IPv6:2a03:3100:c:13:0:0:0:5]) by hz.grosbein.net (8.15.2/8.15.2) with ESMTPS id xASB4lT1065042 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 28 Nov 2019 11:04:50 GMT (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: wjw@digiware.nl Received: from [10.58.0.4] ([10.58.0.4]) by eg.sd.rdtc.ru (8.15.2/8.15.2) with ESMTPS id xASB4iFY036634 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Thu, 28 Nov 2019 18:04:44 +0700 (+07) (envelope-from eugen@grosbein.net) Subject: Re: Process in T state does not want to die..... To: Willem Jan Withagen , FreeBSD Hackers References: <966f830c-bf09-3683-90da-e70aa343cc16@digiware.nl> <3c57e51d-fa36-39a3-9691-49698e8d2124@grosbein.net> <91490c30-45e9-3c38-c55b-12534fd09e28@digiware.nl> From: Eugene Grosbein Message-ID: <0d698f4e-decf-8d4b-7a05-d5985558fb07@grosbein.net> Date: Thu, 28 Nov 2019 18:04:39 +0700 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <91490c30-45e9-3c38-c55b-12534fd09e28@digiware.nl> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Spam-Flag: YES X-Spam-Status: Yes, score=6.0 required=5.0 tests=BAYES_00, DATE_IN_FUTURE_96_Q, HELO_MISC_IP,LOCAL_FROM,RDNS_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.2 X-Spam-Report: * -2.3 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * 2.7 DATE_IN_FUTURE_96_Q Date: is 4 days to 4 months after Received: * date * -0.0 SPF_PASS SPF: sender matches SPF record * 1.9 RDNS_NONE Delivered to internal network by a host with no rDNS * 2.6 LOCAL_FROM From my domains * 1.1 HELO_MISC_IP Looking for more Dynamic IP Relays X-Spam-Level: ***** X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on eg.sd.rdtc.ru X-Rspamd-Queue-Id: 47Nvyv2kRpz4RHt X-Spamd-Bar: + Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=permerror (mx1.freebsd.org: domain of eugen@grosbein.net uses mechanism not recognized by this client) smtp.mailfrom=eugen@grosbein.net X-Spamd-Result: default: False [1.30 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-0.96)[-0.960,0]; SPAM_FLAG(5.00)[]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_LONG(-0.98)[-0.981,0]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[grosbein.net]; RCVD_COUNT_THREE(0.00)[3]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; R_SPF_PERMFAIL(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; IP_SCORE(-1.66)[ip: (-4.38), ipnet: 2a01:4f8::/29(-2.33), asn: 24940(-1.57), country: DE(-0.01)]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:24940, ipnet:2a01:4f8::/29, country:DE]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Nov 2019 11:08:56 -0000 28.11.2019 17:37, Willem Jan Withagen wrote: >> Process in state T is STOPPED and prohibited for execution. >> It cannot even process signal like SIGTERM or SIGKILL because they are queied waiting for continuation. >> You need to resume it with kill -CONT first. > > Tried that several times, but does not really have any effect. > I could check and see if the signals (TERM, KILL) were waiting somewhere? > With procstat?? > > But the original question was more for a way on preventing this state of affairs. > Because uptill now the only resolution was to reboot the server, which is not a nice > thing for a storage sollution. > > Hence the: how to debug? question. Sometimes background process is (mistakenly) started without closing/redirecting output and if it tries to print something, it might get stopped depending on used shell. Use ktrace/kdump to verify what's going on with the process if you can reproduce the problem. You did not specify which version you use. Sometimes flags shown by ps are wrong due to kernel bugs and corrupted process state flag and process is not really Stopped but Exiting for example. ktrace/kdump should show if process got SIGSTOP/SIGTSTP really. And if SIGCONT was delivered.