From owner-freebsd-current@FreeBSD.ORG Fri Jun 24 10:30:19 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (unknown [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3E1F51065673 for ; Fri, 24 Jun 2011 10:30:19 +0000 (UTC) (envelope-from pho@holm.cc) Received: from relay01.pair.com (relay01.pair.com [209.68.5.15]) by mx1.freebsd.org (Postfix) with SMTP id EC3C68FC14 for ; Fri, 24 Jun 2011 10:30:18 +0000 (UTC) Received: (qmail 67517 invoked from network); 24 Jun 2011 10:30:17 -0000 Received: from 87.58.145.224 (HELO x2.osted.lan) (87.58.145.224) by relay01.pair.com with SMTP; 24 Jun 2011 10:30:17 -0000 X-pair-Authenticated: 87.58.145.224 Received: from x2.osted.lan (localhost [127.0.0.1]) by x2.osted.lan (8.14.4/8.14.4) with ESMTP id p5OAUGRe072051; Fri, 24 Jun 2011 12:30:16 +0200 (CEST) (envelope-from pho@x2.osted.lan) Received: (from pho@localhost) by x2.osted.lan (8.14.4/8.14.4/Submit) id p5OAUGY9072050; Fri, 24 Jun 2011 12:30:16 +0200 (CEST) (envelope-from pho) Date: Fri, 24 Jun 2011 12:30:16 +0200 From: Peter Holm To: Kostik Belousov Message-ID: <20110624103016.GA71991@x2.osted.lan> References: <20110623163109.GA508@dragon.NUXI.org> <20110623202153.GS48734@deviant.kiev.zoral.com.ua> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110623202153.GS48734@deviant.kiev.zoral.com.ua> User-Agent: Mutt/1.4.2.3i Cc: freebsd-current@freebsd.org Subject: Re: Thoughts on TMPFS no longer being considered "highly experimental" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Fri, 24 Jun 2011 10:30:19 -0000 On Thu, Jun 23, 2011 at 11:21:53PM +0300, Kostik Belousov wrote: > On Thu, Jun 23, 2011 at 09:31:09AM -0700, David O'Brien wrote: > > Does anyone object to this patch? > > > > David Wolfskill and I have run TMPFS on a number of machines for two > > years with no problems. > > > > I may have missed something, but I'm not aware of any serious PRs on > > TMPFS either. > > > > > > Index: tmpfs_vfsops.c > > =================================================================== > > --- tmpfs_vfsops.c (revision 221113) > > +++ tmpfs_vfsops.c (working copy) > > @@ -155,9 +155,6 @@ tmpfs_mount(struct mount *mp) > > return EOPNOTSUPP; > > } > > > > - printf("WARNING: TMPFS is considered to be a highly experimental " > > - "feature in FreeBSD.\n"); > > - > > vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY); > > error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred); > > VOP_UNLOCK(mp->mnt_vnodecovered, 0); > > The things I am aware of: > - there is a races on the lookup. They were papered over in r212305, > but the bug was not really fixed, AFAIR. > > - the tmpfs does double-buffering for the mapped vnodes. This is quite > insulting for the memory-backed fs, isn't it ? I have a patch, but it is > still under review. > > - I believe Peter Holm has more test cases that fails with tmpfs. He > would have more details. I somewhat remember some panic on execve(2) the > binary located on tmpfs. > I ran the TMPFS tests I have and so far I only spotted the mmap(2) problem: http://people.freebsd.org/~pho/stress/log/tmpfs/ > Removing the warning will not make the issues coming away. > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.11 (FreeBSD) > > iEYEARECAAYFAk4DoGEACgkQC3+MBN1Mb4j9wwCg0V37VuQUw5heAl/Z/iAlO+h0 > SmAAoJf/+BF533SS0hUjGsscsSAqUApX > =5GKO > -----END PGP SIGNATURE----- -- Peter