From owner-freebsd-current Tue Nov 10 17:11:27 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA16693 for freebsd-current-outgoing; Tue, 10 Nov 1998 17:11:27 -0800 (PST) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from burka.carrier.kiev.ua (burka.carrier.kiev.ua [193.193.193.107]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA16686 for ; Tue, 10 Nov 1998 17:11:23 -0800 (PST) (envelope-from archer@grape.carrier.kiev.ua) Received: from grape.carrier.kiev.ua (root@grape.carrier.kiev.ua [193.193.193.219]) by burka.carrier.kiev.ua (8.9.0/8.Who.Cares) with ESMTP id DAA04714; Wed, 11 Nov 1998 03:10:54 +0200 (EET) (envelope-from archer@grape.carrier.kiev.ua) Received: (from archer@localhost) by grape.carrier.kiev.ua (8.9.1/8.9.1) id CAA01861; Wed, 11 Nov 1998 02:38:38 +0200 (EET) (envelope-from archer) Date: Wed, 11 Nov 1998 02:38:38 +0200 (EET) From: Alexander Litvin Message-Id: <199811110038.CAA01861@grape.carrier.kiev.ua> To: Alexander Litvin Cc: current@FreeBSD.ORG Subject: Re: The infamous dying daemons bug X-Newsgroups: grape.freebsd.current In-Reply-To: <199811101456.QAA28210@grape.carrier.kiev.ua> Organization: Lucky Grape User-Agent: tin/pre-1.4-980818 ("Laura") (UNIX) (FreeBSD/3.0-CURRENT (i386)) Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In article <199811101456.QAA28210@grape.carrier.kiev.ua> you wrote: >>> Nov 10 03:15:34 grape /kernel: swap_pager: suggest more swap space: 61 MB >>> Nov 10 03:16:26 grape /kernel: pid 310 (sendmail), uid 0: exited on signal 11 >>> Nov 10 03:17:26 grape /kernel: pid 311 (sendmail), uid 0: exited on signal 11 >>> Nov 10 03:18:25 grape /kernel: pid 313 (sendmail), uid 0: exited on signal 11 >>> Nov 10 03:19:25 grape /kernel: pid 353 (sendmail), uid 0: exited on signal 11 >>> Nov 10 03:20:26 grape /kernel: pid 394 (sendmail), uid 0: exited on signal 11 GL>> Ah, now that's one that I've been getting without exhausting memory. GL>> I'm assuming that these dying sendmails are children of the daemon. GL>> What happens when you kill -1 the daemon ("accepting connections on GL>> port 25 (sendmail)")? In my experience, it *always* dies with a GL>> SIGSEGV after these messages have occurred. AL> Well, as I understand, 'swap_pager: suggest more swap space' does AL> not mean that memory is exhausted, but only that it is about to AL> be exhausted. At least, in this case it didn't come to any processes AL> being killed by kernel. AL> You're right -- that sendmails were childs of a daemon (queue runners). AL> I'm not sure about what happens if I send SIGHUP to the daemon. I AL> think it may or may not restart -- it depends. Last time I examined AL> a 'deseased' daemon (it was not sendmail, but a dummy daemon written AL> specially for testing), it appeared that some range of process memory, AL> where code of dynamic library lives, was corrupt (zeroed in that case). AL> I'll try later to kill -1 such daemon. Now I'm in the process of testing AL> Dima's kludge. Until now I was unable to reproduce a problem. Daemons AL> keep living ;) Brought up old kernel without kludge. It appears that memory corruption leading to 'daemons dying' may take different forms. E.g., once it appears that sendmail continues to fork for queue runs successfully, but when I do 'telnet localhost 25', it just accepts connection, forks, changes proctitle ('startup with ...'), and goes into some strange state -- no EHLO, just accepts all I type in telnet and that's all. In that state kill -1 restarts sendmail ok. Other time I exhaust memory, sendmail segfaults every child forked for queue run, again restarts ok on SIGHUP. Once I even got in responce to 'telnet localhost 25': Trying 127.0.0.1... Connected to localhost.carrier.kiev.ua. Escape character is '^]'. archer... Recipient names must be specified As if I started sendmail without arguments on command prompt! I think it is ehough evidence that 'daemons dying' is caused by memory corruption. GL>> Greg GL>> -- GL>> See complete headers for address, home page and phone numbers GL>> finger grog@lemis.com for PGP public key --- I really hate this damned machine I wish that they would sell it. It never does quite what I want But only what I tell it. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message