From owner-freebsd-gecko@freebsd.org Mon Sep 18 20:38:21 2017 Return-Path: Delivered-To: freebsd-gecko@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 84D66E0598D for ; Mon, 18 Sep 2017 20:38:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.ysv.freebsd.org (unknown [127.0.1.3]) by mx1.freebsd.org (Postfix) with ESMTP id 6D0FB7F0CD for ; Mon, 18 Sep 2017 20:38:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id 6949EE0598C; Mon, 18 Sep 2017 20:38:21 +0000 (UTC) Delivered-To: gecko@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 68E28E0598B for ; Mon, 18 Sep 2017 20:38:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 57B847F0CB for ; Mon, 18 Sep 2017 20:38:21 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id v8IKcKGR051828 for ; Mon, 18 Sep 2017 20:38:21 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: gecko@FreeBSD.org Subject: [Bug 222356] www/firefox: file-backed shared memory performance Date: Mon, 18 Sep 2017 20:38:21 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Ports & Packages X-Bugzilla-Component: Individual Port(s) X-Bugzilla-Version: Latest X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: kib@FreeBSD.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: gecko@FreeBSD.org X-Bugzilla-Flags: maintainer-feedback? X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-gecko@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Gecko Rendering Engine issues List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 18 Sep 2017 20:38:21 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D222356 --- Comment #11 from Konstantin Belousov --- (In reply to Tijl Coosemans from comment #10) The normal writes, as well as writes initiated by the pagedaemon pageouts, = must be allowed even for unlinked vnodes. It is possible that the system is low either on memory, or as is in the case of your backtrace, short of the non-dirty reusable buffers, which cause writes. In this case pages can be reused and we still need the page content, because the process with open ha= ndle might access the paged out page again. Your patch for kern_fsync() looks fine, but I did not looked at it in some details. Since we lock the vnode on normal path, I prefer to not be racy t= here and check for VV_NOSYNC after the vnode is locked. --=20 You are receiving this mail because: You are the assignee for the bug.=