From owner-svn-src-head@FreeBSD.ORG Mon Jan 26 20:11:53 2009 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8D4FB1065670; Mon, 26 Jan 2009 20:11:53 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.terabit.net.ua (mail.terabit.net.ua [195.137.202.147]) by mx1.freebsd.org (Postfix) with ESMTP id 242E48FC25; Mon, 26 Jan 2009 20:11:52 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from skuns.zoral.com.ua ([91.193.166.194] helo=mail.zoral.com.ua) by mail.terabit.net.ua with esmtps (TLSv1:AES256-SHA:256) (Exim 4.63 (FreeBSD)) (envelope-from ) id 1LRXoE-000PxK-Ja; Mon, 26 Jan 2009 22:11:50 +0200 Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id n0QKBk8l032919 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 26 Jan 2009 22:11:46 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.3/8.14.3) with ESMTP id n0QKBkq4001103; Mon, 26 Jan 2009 22:11:46 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.3/8.14.3/Submit) id n0QKBksI001102; Mon, 26 Jan 2009 22:11:46 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Mon, 26 Jan 2009 22:11:46 +0200 From: Kostik Belousov To: David Schultz Message-ID: <20090126201146.GD2009@deviant.kiev.zoral.com.ua> References: <200901230058.n0N0wEjY026935@svn.freebsd.org> <20090125162123.GB17198@hoeg.nl> <20090126041926.J43097@delplex.bde.org> <20090125175751.GC17198@hoeg.nl> <20090126051910.E2148@besplex.bde.org> <20090126190310.GA31728@zim.MIT.EDU> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Km1U/tdNT/EmXiR1" Content-Disposition: inline In-Reply-To: <20090126190310.GA31728@zim.MIT.EDU> User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: ClamAV version 0.94.2, clamav-milter version 0.94.2 on skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua X-Virus-Scanned: mail.terabit.net.ua 1LRXoE-000PxK-Ja 889438f64eadba0efe29647fe13d7c05 X-Terabit: YES Cc: Ed Schouten , src-committers@freebsd.org, Tom Rhodes , svn-src-all@freebsd.org, Bruce Evans , svn-src-head@freebsd.org Subject: Re: svn commit: r187607 - head/usr.bin/truss X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Jan 2009 20:11:54 -0000 --Km1U/tdNT/EmXiR1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jan 26, 2009 at 02:03:10PM -0500, David Schultz wrote: > On Mon, Jan 26, 2009, Bruce Evans wrote: > > - P_SYSTEM has something to do with swapping, and I also removed the > > PS_INMEM setting for init. I have always used NO_SWAPPING and haven't > > used a swap partition since memory sizes reached 64MB, so I wouldn't > > have noticed problems with this. init doesn't run often so it is > > quite likely to be swapped (if allowed to) if real memory runs out. >=20 > Process kstack swapping was removed several years ago, so > "swapping out" a process just deactivates all of its pages. > In principle this could be safe to do with init, but it's probably > a bad idea, and perhaps could lead to deadlock in the > out-of-swap-space -> kill a process -> reparent the zombie to init > path. PS_INMEM will prevent init from being swapped out. Process kernel stacks swapping, or more explicitely, allowance to page out threads kernel stacks, is in the kernel. It is performed by vmdaemon, look for the call to swapout_procs(). Kernel stack contains pcb, but not the struct thread. Notifying the target process about raised signal requires only struct proc and referenced structures (p_sigact, p_sigqueue etc) that cannot be paged out. More interesting propery of the P_SYSTEM process is the immunity to the oom killer. But vm_pageout_oom() explicitely cares to not kill pid 1 or pid < 48. P.S. Your Mail-Followup-To: header may be considered offensive. --Km1U/tdNT/EmXiR1 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (FreeBSD) iEYEARECAAYFAkl+GQEACgkQC3+MBN1Mb4iRXwCaA2vumXSbwEUGQzVRivIrEHVH a8wAn06B+8q4OSe8EMDqfRa35H7sVDm1 =RN0m -----END PGP SIGNATURE----- --Km1U/tdNT/EmXiR1--