From owner-freebsd-current@FreeBSD.ORG Mon Nov 10 09:47:34 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B2E7416A4CE for ; Mon, 10 Nov 2003 09:47:34 -0800 (PST) Received: from mailman.zeta.org.au (mailman.zeta.org.au [203.26.10.16]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3570943F3F for ; Mon, 10 Nov 2003 09:47:33 -0800 (PST) (envelope-from bde@zeta.org.au) Received: from gamplex.bde.org (katana.zip.com.au [61.8.7.246]) by mailman.zeta.org.au (8.9.3p2/8.8.7) with ESMTP id EAA15695; Tue, 11 Nov 2003 04:46:48 +1100 Date: Tue, 11 Nov 2003 04:46:47 +1100 (EST) From: Bruce Evans X-X-Sender: bde@gamplex.bde.org To: "Michael W. Lucas" In-Reply-To: <20031110164513.GA828@bewilderbeast.blackhelicopters.org> Message-ID: <20031111042518.I857@gamplex.bde.org> References: <20031110164513.GA828@bewilderbeast.blackhelicopters.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: current@freebsd.org Subject: Re: erroneous message from locked-up machine X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Nov 2003 17:47:34 -0000 On Mon, 10 Nov 2003, Michael W. Lucas wrote: > I came in to work today to find one of my -current machines unable to > open a pipe. (This probably had a lot to do with the spamd that went > stark raving nutters overnight, but that's a separate problem.) A > power cycle fixed the problem, but /var/log/messages was filled with: > > Nov 10 11:05:44 bewilderbeast kernel: kern.maxpipekva exceeded, please see tuning(7). > > Interesting. > > bewilderbeast~;sysctl kern.maxpipekva > sysctl: unknown oid 'kern.maxpipekva' > bewilderbeast~; The following patch fixes this and some nearby style bugs: - source style bug: line too line - output style bugs: comma splice, verboseness (helps make the source line too long), and kernel message terminated with a ".". %%% Index: sys_pipe.c =================================================================== RCS file: /home/ncvs/src/sys/kern/sys_pipe.c,v retrieving revision 1.158 diff -u -2 -r1.158 sys_pipe.c --- sys_pipe.c 9 Nov 2003 09:17:24 -0000 1.158 +++ sys_pipe.c 10 Nov 2003 17:21:47 -0000 @@ -331,5 +331,5 @@ if (error != KERN_SUCCESS) { if (ppsratecheck(&lastfail, &curfail, 1)) - printf("kern.maxpipekva exceeded, please see tuning(7).\n"); + printf("kern.ipc.maxpipekva exceeded; see tuning(7)\n"); return (ENOMEM); } %%% > And tuning(7) doesn't mention this, either. > > Is this just work-in-progress, or did someone forget to commit something? Seems like tuning pipe kva is completely absent in tuning(7) (so the above message can be shortened further). You can tune kva generally as documented there, but the pipe limit is separate. > PS: Lesson of the day: no pipe KVA, no su. Great fun on remote > machines! :-) It's interesting that su was the point of failure. It uses a pipe hack for IPC. Otherwise it doesn't use pipes, at least direectly. It shouldn't need to use the pipe hack. My version uses signals instead. Bruce