earlyoom: Add vlab-earlyoom-static and update notify script

vlab-earlyoom-static/DEBIAN/control

@@ -0,0 +1,11 @@
+Package: vlab-earlyoom-static
+Version: 1.1-5
+Section: base
+Priority: optional
+Architecture: amd64
+Recommends: zenity
+Provides: earlyoom
+Conflicts: earlyoom, vlab-earlyoom
+Replaces: earlyoom, vlab-earlyoom
+Maintainer: USTC Vlab <[email protected]>
+Description: Vlab earlyoom configurations for interactive responsiveness, with static earlyoom binary

vlab-earlyoom-static/DEBIAN/postinst

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+echo "Enabling and starting vlab-earlyoom.service..."
+systemctl enable --now vlab-earlyoom.service || true

vlab-earlyoom-static/DEBIAN/preinst

@@ -0,0 +1,19 @@
+#!/bin/sh
+set -e
+
+PACKAGE=vlab-earlyoom
+
+case "$1" in
+  install)
+    systemctl unmask earlyoom.service || true
+    ;;
+  upgrade|abort-upgrade)
+    systemctl unmask earlyoom.service || true
+    ;;
+  *)
+    echo "preinst called with unknown argument \`$1'" >&2
+    exit 0
+    ;;
+esac
+#DEBHELPER#
+exit 0

vlab-earlyoom-static/etc/default/earlyoom

@@ -0,0 +1,2 @@
+# Options to pass to earlyoom
+EARLYOOM_ARGS="-r 60 -m 5,4 -s 5 --avoid sshd -N /etc/vlab/earlyoom-notif.sh"

vlab-earlyoom-static/etc/vlab/earlyoom-notif.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+MSG="由于内存不足，earlyoom 已结束进程 $EARLYOOM_NAME 以保证用户界面流畅。如果多次看到此消息，请联系管理员添加内存。"
+
+RATELIMIT="/tmp/earlyoom-ratelimit"
+
+(
+    flock -x 200 -w 2
+    if [ -f "$RATELIMIT" ]; then
+        CURRENT=$(date +%s)
+        FILE=$(stat -c %Y "$RATELIMIT")
+
+        DIFF=$((CURRENT-FILE))
+        # 10 seconds rate-limit
+        if [ "$DIFF" -lt 10 ]; then
+            echo "Rate-limited earlyoom notification"
+            exit 0
+        fi
+    fi
+    touch "$RATELIMIT"
+) 200>"$RATELIMIT"
+
+wall "$MSG"
+date >> /tmp/earlyoom-record
+if ! command -v zenity &> /dev/null; then
+    exit 0
+fi
+
+if id "ubuntu" &>/dev/null; then
+    USER="ubuntu"
+else
+    USER="vlab"
+fi
+
+DISPLAY=:0 sudo -u "$USER" zenity --error --text "$MSG" &

vlab-earlyoom-static/lib/systemd/system/vlab-earlyoom.service

@@ -0,0 +1,17 @@
+[Unit]
+Description=Early OOM Daemon in Vlab environment
+Documentation=man:earlyoom(1) https://github.com/rfjakob/earlyoom
+
+[Service]
+EnvironmentFile=-/etc/default/earlyoom
+ExecStart=/usr/bin/earlyoom $EARLYOOM_ARGS
+# earlyoom never exits on it's own, so have systemd
+# restart it should it get killed for some reason.
+Restart=always
+# set memory limits and max tasks number
+TasksMax=10
+MemoryMax=50M
+
+[Install]
+WantedBy=multi-user.target
+Alias=earlyoom.service

vlab-earlyoom/DEBIAN/control

@@ -1,11 +1,11 @@
 Package: vlab-earlyoom
-Version: 1.1-4
+Version: 1.1-5
 Section: base
 Priority: optional
 Architecture: all
 Recommends: zenity
 Provides: earlyoom
-Conflicts: earlyoom
-Replaces: earlyoom
+Conflicts: earlyoom, vlab-earlyoom-static
+Replaces: earlyoom, vlab-earlyoom-static
 Maintainer: USTC Vlab <[email protected]>
 Description: Vlab earlyoom configurations for interactive responsiveness

vlab-earlyoom/etc/vlab/earlyoom-notif.sh

@@ -22,4 +22,14 @@ RATELIMIT="/tmp/earlyoom-ratelimit"
 
 wall "$MSG"
 date >> /tmp/earlyoom-record
-DISPLAY=:0 sudo -u ubuntu zenity --error --text "$MSG" &
+if ! command -v zenity &> /dev/null; then
+    exit 0
+fi
+
+if id "ubuntu" &>/dev/null; then
+    USER="ubuntu"
+else
+    USER="vlab"
+fi
+
+DISPLAY=:0 sudo -u "$USER" zenity --error --text "$MSG" &