From owner-freebsd-current@FreeBSD.ORG Tue Apr 22 20:37:01 2008 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 63BDC106564A for ; Tue, 22 Apr 2008 20:37:01 +0000 (UTC) (envelope-from tataz@tataz.chchile.org) Received: from smtp5-g19.free.fr (smtp5-g19.free.fr [212.27.42.35]) by mx1.freebsd.org (Postfix) with ESMTP id 2B1BF8FC32 for ; Tue, 22 Apr 2008 20:37:00 +0000 (UTC) (envelope-from tataz@tataz.chchile.org) Received: from smtp5-g19.free.fr (localhost.localdomain [127.0.0.1]) by smtp5-g19.free.fr (Postfix) with ESMTP id 91C923F6161; Tue, 22 Apr 2008 22:36:59 +0200 (CEST) Received: from tatooine.tataz.chchile.org (tataz.chchile.org [82.233.239.98]) by smtp5-g19.free.fr (Postfix) with ESMTP id 5FF8A3F61B1; Tue, 22 Apr 2008 22:36:58 +0200 (CEST) Received: from obiwan.tataz.chchile.org (unknown [192.168.1.25]) by tatooine.tataz.chchile.org (Postfix) with ESMTP id 0686F9BF12; Tue, 22 Apr 2008 20:34:36 +0000 (UTC) Received: by obiwan.tataz.chchile.org (Postfix, from userid 1000) id E9D6D405B; Tue, 22 Apr 2008 22:34:35 +0200 (CEST) Date: Tue, 22 Apr 2008 22:34:35 +0200 From: Jeremie Le Hen To: freebsd-current@FreeBSD.org Message-ID: <20080422203435.GA92168@obiwan.tataz.chchile.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.15 (2007-04-06) Cc: Daichi GOTO , Masanori OZAWA Subject: unionfs makes -CURRENT very sluggish 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: Tue, 22 Apr 2008 20:37:01 -0000 Hi, I tried to compile lib/ncurses through unionfs. It is utterly slow, no matter I mount with noatime or not. Relevant mounts: % /usr/src on /space/chroot/usr/src (nullfs, local, read-only) % :/space/chroot/usr/src.union on /space/chroot/usr/src (unionfs, local) % root:~# chroot /space/chroot % root:/# cd /usr/src/ % root:/# make buildenv % # cd lib/ncurses % # time make Compile time without noatime: 5089.47 real 1670.72 user 3364.89 sys Compile time with noatime: 5083.22 real 1664.10 user 3369.22 sys Now if I remove the unionfs mount and just use nullfs: 255.47 real 150.51 user 83.82 sys As you can see, most of the time is spent in kernel. I'm recompiling my kernel with hwpmc right now in order to profile it. Any other debug hint would be welcome. FWIW, "while sleep 1 ; do date ; done" runs jerkily when unionfs is run: Tue Apr 22 21:20:06 CEST 2008 Tue Apr 22 21:20:13 CEST 2008 Tue Apr 22 21:20:17 CEST 2008 Tue Apr 22 21:20:22 CEST 2008 Tue Apr 22 21:20:29 CEST 2008 Whereas it runs smoothly without unionfs. I'll give the result of hwpmc ASAP. Best regards, -- Jeremie Le Hen < jeremie at le-hen dot org >< ttz at chchile dot org >