From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D6DDC43381 for ; Thu, 21 Mar 2019 10:27:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCA41218D3 for ; Thu, 21 Mar 2019 10:27:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727867AbfCUK1t (ORCPT ); Thu, 21 Mar 2019 06:27:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40122 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725985AbfCUK1t (ORCPT ); Thu, 21 Mar 2019 06:27:49 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id ABC643086250; Thu, 21 Mar 2019 10:27:48 +0000 (UTC) Received: from work (ovpn-204-90.brq.redhat.com [10.40.204.90]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8E6825D9C4; Thu, 21 Mar 2019 10:27:47 +0000 (UTC) Date: Thu, 21 Mar 2019 11:27:42 +0100 From: Lukas Czerner To: Theodore Ts'o Cc: Ext4 Developers List , darrick.wong@oracle.com Subject: Re: [PATCH 8/9] e2scrub_all: refactor device probe loop Message-ID: <20190321102742.k2oos4epoj6fyjao@work> References: <20190321020218.5154-1-tytso@mit.edu> <20190321020218.5154-8-tytso@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190321020218.5154-8-tytso@mit.edu> User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Thu, 21 Mar 2019 10:27:48 +0000 (UTC) Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed, Mar 20, 2019 at 10:02:17PM -0400, Theodore Ts'o wrote: > From: "Darrick J. Wong" > > Paul Menzel reported that the e2scrub_all reaper service that runs at > startup takes a long time to run, and Ted Ts'o pointed out that we could > do a lot less work by using lvs as the outer loop in the ext4 filesystem > probe function so that we only have to lsblk the lvm devices containing > ext4 filesystems. > > Therefore, refactor the loops to put lvs first, which should boost speed > a bit. > > [ Made some of the further optimizations suggested by Lukas Czerner. -- TYT ] > > Reported-by: Paul Menzel > Signed-off-by: Darrick J. Wong > Signed-off-by: Theodore Ts'o > --- > scrub/e2scrub_all.in | 34 +++++++++++++++++++++++----------- > 1 file changed, 23 insertions(+), 11 deletions(-) > > diff --git a/scrub/e2scrub_all.in b/scrub/e2scrub_all.in > index 4cb90a0de..cad232987 100644 > --- a/scrub/e2scrub_all.in > +++ b/scrub/e2scrub_all.in > @@ -22,6 +22,7 @@ PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin > > scrub_all=0 > snap_size_mb=256 > +reap=0 > conffile="@root_sysconfdir@/e2scrub.conf" > > test -f "${conffile}" && . "${conffile}" > @@ -65,7 +66,7 @@ exitcode() { > while getopts "nrAV" opt; do > case "${opt}" in > "n") DBG="echo Would execute: " ;; > - "r") scrub_args="${scrub_args} -r";; > + "r") scrub_args="${scrub_args} -r"; reap=1;; > "A") scrub_all=1;; > "V") print_version; exitcode 0;; > *) print_help; exitcode 2;; > @@ -88,9 +89,12 @@ if ! type lvcreate >& /dev/null ; then > fi > > # Find scrub targets, make sure we only do this once. > -ls_scrub_targets() { > - lsblk -o NAME,FSTYPE,MOUNTPOINT -p -P -n | while read vars; do > +ls_scan_targets() { > + lvs --name-prefixes -o vg_name,lv_path \ > + -S lv_active=active,lv_role=public --noheadings | \ > + while read vars; do > eval "${vars}" > + eval "$(lsblk -o FSTYPE,MOUNTPOINT -p -P -n "${LVM2_LV_PATH}")" > > # Skip non-ext[234] > case "${FSTYPE}" in > @@ -103,12 +107,6 @@ ls_scrub_targets() { > continue; > fi > > - # Skip non-lvm devices and lvm snapshots > - lvm_vars="$(lvs --nameprefixes -o vg_name,lv_name,lv_role --noheadings "${NAME}" 2> /dev/null)" > - test $? -ne 0 && continue > - eval "${lvm_vars}" > - echo "${LVM2_LV_ROLE}" | grep -q "snapshot" && continue This is wrong. lvs --name-prefixes -o vg_name,lv_path \ -S lv_active=active,lv_role=public --noheadings | \ lv_role=public does not exclude snapshots and so it will fail later in e2scrub when you try to create a snapshot of a thicksnapshot which is not supported. Snapshot of a thinspanshot is allowed though, so we might want to include those. Not sure if it's wise to do it by default, but regardless it's probably something for a separate change. Also I am not sure what's the rush, but it seems you've ignored my other suggestions. -Lukas > - > free_space="$(vgs -o vg_free --units m --noheadings --no-suffix "${LVM2_VG_NAME}" 2> /dev/null | sed -e 's/\..*//')" > test "${snap_size_mb}" -gt "${free_space}" && continue > > @@ -120,6 +118,20 @@ ls_scrub_targets() { > done | sort | uniq > } > > +# Find leftover scrub snapshots > +ls_reap_targets() { > + lvs -o lv_path -S lv_role=snapshot -S lv_name=~\(e2scrub$\) --noheadings > +} > + > +# Figure out what we're targeting > +ls_targets() { > + if [ "${reap}" -eq 1 ]; then > + ls_reap_targets > + else > + ls_scan_targets > + fi > +} > + > # systemd doesn't know to do path escaping on the instance variable we pass > # to the e2scrub service, which breaks things if there is a dash in the path > # name. Therefore, do the path escaping ourselves if needed. > @@ -140,10 +152,10 @@ escape_path_for_systemd() { > > # Scrub any mounted fs on lvm by creating a snapshot and fscking that. > stdin="$(realpath /dev/stdin)" > -ls_scrub_targets | while read tgt; do > +ls_targets | while read tgt; do > # If we're not reaping and systemd is present, try invoking the > # systemd service. > - if [ -z "${scrub_args}" ] && type systemctl > /dev/null 2>&1; then > + if [ "${reap}" -ne 1 ] && type systemctl > /dev/null 2>&1; then > tgt_esc="$(escape_path_for_systemd "${tgt}")" > ${DBG} systemctl start "e2scrub@${tgt_esc}" 2> /dev/null < "${stdin}" > res=$? > -- > 2.19.1 >