X-Git-Url: https://iankelling.org/git/?p=distro-setup;a=blobdiff_plain;f=btrfsmaint;h=c410b7b3503359309ab6938f5c233f7193cd6a3e;hp=6c7dbb1f6788119cafa9cac1dc2cae559cd2c07b;hb=HEAD;hpb=b18dade73dedfe69aa741f8417947d83c4208f2d

diff --git a/btrfsmaint b/btrfsmaint
index 6c7dbb1..85f2f34 100755
--- a/btrfsmaint
+++ b/btrfsmaint
@@ -1,102 +1,188 @@
 #!/bin/bash
+# I, Ian Kelling, follow the GNU license recommendations at
+# https://www.gnu.org/licenses/license-recommendations.en.html. They
+# recommend that small programs, < 300 lines, be licensed under the
+# Apache License 2.0. This file contains or is part of one or more small
+# programs. If a small program grows beyond 300 lines, I plan to switch
+# its license to GPL.
+
+# Copyright 2024 Ian Kelling
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 
 
 [[ $EUID == 0 ]] || exec sudo -E "${BASH_SOURCE[0]}" "$@"
 
-source /a/bin/errhandle/err
+set -e; . /usr/local/lib/bash-bear; set +e
 
 # inspired from
 # https://github.com/kdave/btrfsmaintenance
 
+if [[ $INVOCATION_ID ]]; then
+  err-cleanup() {
+    exim -odf -i root <<EOF
+From: root@$(hostname -f)
+To: root@$(hostname -f)
+Subject: btrfsmaint automatically exited on command error
+
+journalctl -u btrfsmaint -n 50:
+$(journalctl -u btrfsmaint -n 50)
+EOF
+  }
+fi
 
-# Man page says we could also use a range, i suppose it would be
-# logical to use a pattern like 5..10 10..20,
-# but I don't know if this would help us at all.
 dusage="5 10"
 musage="5"
 
-e() { echo "cron: $*"; "$@"; }
+e() {
+  echo "btrfsmaint: $*"
+  if ! $dryrun; then
+    "$@"
+  fi
+}
 
 check-idle() {
-  type -p xprintidle &>/dev/null || return 0
+  type -p xscreensaver-command &>/dev/null || return 0
+  export XAUTHORITY=/home/iank/.Xauthority
   export DISPLAY=:0
-  # a hours, a movie could run that long.
-  idle_limit=$((1000 * 60 * 60 * 2))
-  idle_time=$idle_limit
-  while read -r user; do
-    new_idle_time=$(sudo -u $user xprintidle 2>/dev/null) ||:
-    if [[ $new_idle_time && $new_idle_time -lt $idle_time ]]; then
-      idle_time=$new_idle_time
+  locked=false
+  if lock_info=$(xscreensaver-command -time); then
+    if [[ $lock_info != *non-blanked* ]]; then
+      locked=true
     fi
-  done < <(users | tr " " "\n" | sort -u)
-  if (( idle_time < idle_limit )); then
-    idle=false
   else
-    idle=true
+    locked=true
   fi
 }
 
-
 usage() {
   cat <<EOF
-Usage: ${0##*/} args
-Do btrfs maintence or stop if xprintidle shows a user
+Usage: ${0##*/} [OPTIONS]
+Do btrfs maintence or stop if we have X and xprintidle shows a user
+
+Normally, no options are needed.
 
-force  Run regardless of user idle status
-check  Only check if an existing maintence should be cancelled due to
-         nonidle user. Also, runs in a loop every 20 seconds for 10
+--check  Only check if an existing maintence should be cancelled due to
+         nonidle user and run in a loop every 20 seconds for 10
          minutes.
 
+--dryrun Just print out what we would do.
+
+--force  Run regardless of user idle status on all disks and do scrub
+         regardless of when it was last run.
+--no-stats  Avoid checking error statistics. Use this to avoid a rare race
+            condition when running --check concurrently with normal run.
+
+
+-h|--help   Show help
+
 Note: Uses util-linux getopt option parsing: spaces between args and
 options, short options can be combined, options before args.
 EOF
   exit $1
 }
 
+##### begin command line parsing ########
+
+# ensure we can handle args with spaces or empty.
+ret=0; getopt -T || ret=$?
+[[ $ret == 4 ]] || { echo "Install util-linux for enhanced getopt" >&2; exit 1; }
 
-force=false
 check=false
-if [[ $1 ]]; then
+dryrun=false
+force=false
+stats=true
+
+temp=$(getopt -l help,check,dryrun,force,no-stats h "$@") || usage 1
+eval set -- "$temp"
+while true; do
   case $1 in
-    check)
-      check=true
-      ;;
-    force)
-      force=true
-      ;;
-    *)
-      echo "$0: error: unexpected arg" >&2
-      usage 1
-      ;;
+    --check) check=true ;;
+    --dryrun) dryrun=true ;;
+    --force) force=true ;;
+    --no-stats) stats=false ;;
+    -h|--help) usage ;;
+    --) shift; break ;;
+    *) echo "$0: unexpected args: $*" >&2 ; usage 1 ;;
   esac
-fi
+  shift
+done
+readonly check dryrun force stats
+##### end command line parsing ########
 
 
 main() {
-  idle=true
   if ! $force; then
     check-idle
+    if ! $check; then
+      min=0
+      max_min=300
+      # When the cron kicks in, we may not be idle (physically sleeping) yet, so
+      # wait.
+      while ! $locked && (( min < max_min )); do
+        min=$(( min + 1 ))
+        sleep 60
+        check-idle
+      done
+      # If we've waited a really long time for idle, just give up.
+      if (( min == max_min )); then
+        return
+      fi
+    fi
   fi
 
-  tmp=$(mktemp)
 
   fnd="findmnt --types btrfs --noheading"
   for x in $($fnd --output "SOURCE" --nofsroot | sort -u); do
     mnt=$($fnd --output "TARGET" --first-only --source $x)
     [[ $mnt ]] || continue
 
-    if ! btrfs dev stats -c $mnt >$tmp; then
-      if diff -q $mnt/btrfs-dev-stats $tmp; then
-        diff -u $mnt/btrfs-dev-stats $tmp | mail -s "$HOSTNAME: error: btrfs dev stats -c $mnt" root@localhost
-        cat $tmp >$mnt/btrfs-dev-stats
+    #### begin look for diff in stats, eg: increasing error count ####
+    if $stats; then
+      tmp=$(mktemp)
+      # ${mnt%/} so that if mnt is / we avoid making a buggy looking path
+      stats_path=${mnt%/}/btrfs-dev-stats
+      if [[ ! -e $stats_path ]]; then
+        btrfs dev stats -c $mnt >$stats_path ||: # populate initial reading
+      elif ! btrfs dev stats -c $mnt >$tmp; then
+        if ! diff -q $stats_path $tmp; then
+          mv $stats_path $stats_path.1
+          cat $tmp >$stats_path
+          diff=$(diff -u $stats_path $tmp 2>&1 ||:)
+          printf "diff of: btrfs dev stats -c %s\n%s\n" "$mnt" "$diff"
+          exim -odf -i root <<EOF
+From: root@$(hostname -f)
+To: root@$(hostname -f)
+Subject: btrfsmaint: device stats changed for $mnt
+
+diff of: btrfs dev stats -c $mnt
+$diff
+EOF
+        fi
       fi
+      rm -f $tmp
     fi
+    #### end look for diff in stats, eg: increasing error count ####
 
-    if ! $idle; then
-      btrfs scrub cancel $mnt &>/dev/null ||:
-      continue
-    fi
     if $check; then
+      if ! $locked; then
+        if $dryrun; then
+          echo "$0: not idle. if this wasnt a dry run, btrfs scrub cancel $mnt"
+        else
+          btrfs scrub cancel $mnt &>/dev/null ||:
+        fi
+      fi
       continue
     fi
 
@@ -118,25 +204,42 @@ main() {
         e ionice -c 3 btrfs balance start -musage=$usage $mnt
       done
     fi
-    # e btrfs filesystem df $mnt
-    # e df -H $mnt
-    date=$(
-      btrfs scrub status $mnt | \
-        sed -rn 's/^\s*scrub started at (.*) and finished.*/\1/p'
-        )
-    if [[ $date ]]; then
+    date=
+    scrub_status=$(btrfs scrub status $mnt)
+    if printf "%s\n" "$scrub_status" | grep -i '^status:[[:space:]]*finished$' &>/dev/null; then
+      date=$(printf "%s\n" "$scrub_status" | sed -rn 's/^Scrub started:[[:space:]]*(.*)/\1/p')
+    fi
+    if [[ ! $date ]]; then
+      # output from older versions, at least btrfs v4.15.1
+      date=$(
+        printf "%s\n" "$scrub_status" | \
+          sed -rn 's/^\s*scrub started at (.*) and finished.*/\1/p'
+          )
+    fi
+    if ! $force && [[ $date ]]; then
+      if $dryrun; then
+        echo "$0: last scrub finish for $mnt: $date"
+      fi
       date=$(date --date="$date" +%s)
-      # if date is sooner than 90 days ago
+      # if date is sooner than 60 days ago
       # the wiki recommends 30 days or so, but
-      # it makes the comp lag like shit for a day,
-      # so I'm going with 90 days.
-      if (( date > $(date +%s) - 60*60*24*30 )); then
-        echo "cron: skiping scrub of $mnt"
+      # I'm going with 60 days.
+      if (( date > EPOCHSECONDS - 60*60*24*60 )); then
+        if $dryrun; then
+          echo "$0: skiping scrub of $mnt, last was $(( (EPOCHSECONDS - date) / 60/60/24 )) days ago, < 30 days"
+        fi
         continue
       fi
     fi
-    # -c 2 -n 4 is from btrfsmaintenance, does ionice
-    e btrfs scrub start -Bd -c 2 -n 4 $mnt
+    # btrfsmaintenance does -c 2 -n 4, but I want lowest pri.
+    e btrfs scrub start -Bd -c 3 $mnt
+
+    # We normally only do one disk since this is meant to be run in
+    # downtime and if we try to do all disks, we invariably end up doing
+    # a scrub after downtime. So, just do one disk per day.
+    if ! $force; then
+      return 0
+    fi
   done
 }