From owner-svn-src-all@FreeBSD.ORG Tue Oct 7 16:08:22 2014 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 4CB88120; Tue, 7 Oct 2014 16:08:22 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (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 38A767B5; Tue, 7 Oct 2014 16:08:22 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.9/8.14.9) with ESMTP id s97G8MOx067344; Tue, 7 Oct 2014 16:08:22 GMT (envelope-from avg@FreeBSD.org) Received: (from avg@localhost) by svn.freebsd.org (8.14.9/8.14.9/Submit) id s97G8MVc067343; Tue, 7 Oct 2014 16:08:22 GMT (envelope-from avg@FreeBSD.org) Message-Id: <201410071608.s97G8MVc067343@svn.freebsd.org> X-Authentication-Warning: svn.freebsd.org: avg set sender to avg@FreeBSD.org using -f From: Andriy Gapon Date: Tue, 7 Oct 2014 16:08:22 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r272708 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Oct 2014 16:08:22 -0000 Author: avg Date: Tue Oct 7 16:08:21 2014 New Revision: 272708 URL: https://svnweb.freebsd.org/changeset/base/272708 Log: l2arc_write_buffers: reduce headroom value FreeBSD has ARC_BUFC_NUMMETADATALISTS metadata lists and ARC_BUFC_NUMDATALISTS data lists (currently both are 16) while illumos has just a single list of each kind. headroom determines how much data is scanned on a single list during each run of the l2arc feed thread. Because FreeBSD has more lists we proportionally decrease the limit. Reviewed by: Brendan Gregg (earlier version) MFC after: 2 weeks Sponsored by: HybridCluster Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c ============================================================================== --- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c Tue Oct 7 16:06:10 2014 (r272707) +++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c Tue Oct 7 16:08:21 2014 (r272708) @@ -5047,7 +5047,7 @@ l2arc_write_buffers(spa_t *spa, l2arc_de if (ab == NULL) ARCSTAT_BUMP(arcstat_l2_write_buffer_list_null_iter); - headroom = target_sz * l2arc_headroom; + headroom = target_sz * l2arc_headroom * 2 / ARC_BUFC_NUMLISTS; if (do_headroom_boost) headroom = (headroom * l2arc_headroom_boost) / 100;