From owner-freebsd-questions Wed Jul 31 05:19:24 1996 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id FAA25746 for questions-outgoing; Wed, 31 Jul 1996 05:19:24 -0700 (PDT) Received: from relay1.sw.ru (myth.sw.ru [194.190.197.129]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id FAA25729 for ; Wed, 31 Jul 1996 05:19:19 -0700 (PDT) Received: from zeus by relay1.sw.ru (8.6.12/8.6.12/jt) with SMTP id QAA15021; Wed, 31 Jul 1996 16:18:08 +0400 Message-Id: <2.2.32.19960731122407.00b12a5c@myth.sw.ru> X-Sender: jt@myth.sw.ru X-Mailer: Windows Eudora Pro Version 2.2 (32) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 31 Jul 1996 16:24:07 +0400 To: dg@Root.COM From: Juri Tsibrovski Subject: Re: Considering FreeBSD Cc: questions@FreeBSD.ORG Sender: owner-questions@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk At 00:06 29.07.96 -0700, David Greenman wrote: >>On Fri, 26 Jul 1996, Paul J. Mech wrote: >> >>> 0) When Linux runs out of virtual memory, it crashes. What is FreeBSD's >>> behavior under these conditions? >> >>FreeBSD will start killing processes until the memory problem is resolved. >>This usually means the program that is trying to start, and working >>backward. Occaisionally the VM system gets too busy and kills init, but >>that is very rare. > > FreeBSD will never kill init or any process whose process id is less than >48. In the extremely unlikely event that the process consuming all the memory >has a pid less than 48, the system will hang. This is extremely unlikely >because when the pids wrap at 32767, then wrap back to 100, so usually only >processes that were started at system startup time will have pids < 100. > Is 48 a kind of magic number? Last night one of our machines eventually run out of VM, then inetd (pid 91) and tac_plus (authorization and authentification daemon for our terminal servers, pid 190) got killed. Now I'm seriously considering modifying the source code to protect more processes from being killed. So, what's the Pros et Contra, besides the risc of system crash when one of that processes going crazy? Any other solution? --- jt -- just typist :)