Updated for systemd user units, fleshed out INSTALL.md

.gitignore

@@ -0,0 +1,12 @@
+*
+!.gitignore
+!CONFIGURE.md
+!INSTALL.md
+!README.md
+!psi-alerts-user.service
+!psi-alerts.sh
+!psi-alerts@.service
+!psi-by-example
+!psi-monitor-user.service
+!psi-monitor.service
+!psi-monitor.sh

CONFIGURE.md

@@ -1,19 +1,26 @@
-# CONFIGURE
-Included in this project are a number of systemd units:
+# CONFIGURE Included in this project are a number of systemd units:
     * psi-monitor.service
         * uses psi-monitor executable (in /usr/bin/)
-    * psi-alerts@.service (system template service)
-        * uses psi-alerts.sh script
+    * psi-alerts@.service (systemd template service)
+        * uses psi-alerts.sh script in */usr/local/bin/*
+    * psi-alerts-user.service (systemd user service)
+        * also uses psi-alerts.sh script in *~/bin/* (or wherever you want to
+          put it)
 
 The `psi-alerts.sh` is essentially a daemon (a systemd simple service), and for
 now the systemd template needs to be instantiated with the username that will
-execute `psi-alerts.sh`.  Also, a systemd unit override should be created, like
-so:  
+execute `psi-alerts.sh` (if using the systemd template).  Also, a systemd unit
+override should be created, like so:  
 
 ```
+sudo cp psi-alerts@.service /etc/systemd/system/
 sudo systemctl edit psi-alerts@<user>.service
 ```
-
+--OR--
+```
+cp psi-alerts-user.service ~/.config/systemd/user/psi-alerts.service
+systemctl --user edit psi-alerts.service
+```
 This will open an editor, and in later versions of systemd the comment code will be included, clearly showing where the override should be entered:
 
 ```
@@ -25,23 +32,28 @@ Environment=EMAIL_TO="email@domain.tld"
 Environment=SMS_DST="phone_number@sms.domain.tld"
 Environment=NOTIFICATION_CMD="dunstify"
 Environment=NOTIFICATION_OPTS="--timeout=0 --printid --urgency=critical --icon=/usr/share/icons/breeze-dark/emblems/16/emblem-warning.svg"
+Environment=NOTIFICATION_HIST_CMD="dunstctl history"
 Environment=NOTIFICATION_IDX=15
 Environment=SSH_USER="username"
 Environment=SSH_HOST="localhost"
 Environment=SSH_PORT=5999
-Environment=SSH_ID_PATH="~trey/.ssh/psi-alerts"
+Environment=SSH_ID_PATH="~user/.ssh/psi-alerts"
 Environment=CLEAR_THRESHOLD="5.0"
+ExecStart=  # Clear ExecStart for user unit
+ExecStart=/path/to/psi-alerts.sh --user # User unit
 
 ### Edits below this comment will be discarded
 
 ### /etc/systemd/system/psi-alerts@.service
 # [Unit]
 # Description=Pressure Stall Information (PSI) alerts
-# PartOf=multi-user.target
+# PartOf=multi-user.target  # system template
+# PartOf=default.target     # user service
 # After=psi-monitor.service
 #
 # [Service]
-# User=%i
+# 
+# User=%i # User unit will not have User=%i
 # Type=simple
 # ExecStart=psi-alerts.sh
 #
@@ -49,3 +61,40 @@ Environment=CLEAR_THRESHOLD="5.0"
 # WantedBy=multi-user.target
 ```
 
+All of these are required except where noted, there are no default options
+(defaults may be added in the future).  A brief description of each:
+* **EMAIL_TO**:  the email address the notification should be sent to.  The
+  output of `pidstat` will be included in the body of this email, for each
+  triggered resource type (CPU, I/O, Memory), at the time the monitor alerted.
+* **SMS_DST**:  the email-to-SMS address, as defined by your mobile carrier.
+  Please review your mobile carrier's documentation.  For Google Fi, based in
+  the US, the format is
+  `<mobile_number_without_country_code>@msg.fi.google.com`.  This email address
+  does **not** get the output of `pidstat` in the body of the message.
+* **NOTIFICATION_CMD**:   The command on the remote host to run to display
+  notifications, e.g. `notify-send` or `dunstify`.
+* **NOTIFICATION_OPTS**:   Options for the `${NOTIFICATION_CMD}`.  Should
+  include `--print-id` if supported by the command.
+* **NOTIFICATION_HIST_CMD**:  The command to display the notification history
+  (e.g. `dunst history`).
+* **NOTIFICATION_IDX**:  The index if the JSON structure that contains the
+  notification ID.  `dunst`, as of version 1.9.2-1, displays its history as a
+  JSON structure.  For other notification daemons, some other history mechanism
+  will likely be required;  patches needed and welcome!
+* **SSH_USER**:  The SSH username to connect to the remote host that will
+  display the notifications to the system administrator.
+* **SSH_HOST**:  The SSH host to connect to.  This is where
+  `${NOTIFICATION_CMD} ${NOTIFICATION_OPTS}` and `${NOTIFICATION_HIST_CMD}`
+  will run.
+* **SSH_PORT**:  The SSH port to connect to.
+* **SSH_ID_PATH**:  The path to the SSH id (private key file) to use for
+  authenticating to the remote host.  This can be exluded if the local user
+  already has an ssh-agent running, with the necessary key and passphrase
+  entered.  If ssh-agent is not desired, then this SSH id (private key file)
+  should have an empty passphrase (i.e., no passphrase).  Not having this
+  environment variable, and no ssh-agent will disable the desktop notifications
+  (SMS and email will still work, as they don't use SSH)
+* **CLEAR_THRESHOLD**:  The percentage threshold the some avg300 threshold
+  should be below before considering the alert cleared.  This will depend
+  highly on the workload running on the system.
+

INSTALL.md

@@ -4,4 +4,60 @@ First, clone this repository with the `--recurse-submodules` flag:
 $ git clone --recurse-submodules https://git.eldon.me/trey/psi-alerts.git
 ```
 
+`--recurse-submodules` is only necessary if you wish to use the modified
+psi-by-example program for `psi-monitor`.  I found this too noisy to be of use,
+it alerts too quickly so I wrote my own with relaxed timing.
+
+If you want to use the psi-by-example/psi-monitor code, you'll need to compile
+it: 
+
+```
+gcc -o psi-monitor psi-monitor.c
+``` 
+
+## Using the systemd template unit
+1.  Copy the `psi-alerts.sh` and `psi-monitor.sh` scripts to */usr/local/bin*:
+
+    ```
+    sudo cp psi-alerts.sh /usr/local/bin
+    sudo cp psi-monitor.sh /usr/local/bin/psi-monitor 
+    ### OR ###
+    sudo cp psi-by-example/psi-monitor /usr/local/bin
+    ```
+
+2.  Copy the systemd units to */etc/systemd/system*:
+
+    ```
+    sudo cp psi-alerts@.service psi-monitor.service /etc/systemd/system/
+    ```
+
+
+## Using the systemd user units
+1.  Copy the `psi-alerts.sh` and `psi-monitor.sh` scripts to *~/bin* (or
+    wherever you want them):
+    
+    ```
+    cp -a psi-alerts.sh psi-monitor.sh ~/bin/
+    ```
+
+2.  Copy the systemd user units to *~/.config/systemd/user/*
+
+    ```
+    cp psi-alerts-user.service ~/.config/systemd/user/psi-alerts.service
+    cp psi-monitor-user.service ~/.config/systemd/user/psi-monitor.service
+    ```
+
+# CONFIGURE
+See *CONFIGURE.md* in this repository
+
+# ENABLE and START
+## system template instance:
+```
+sudo systemctl enable --now psi-monitor.service psi-alerts@<user>.service
+```
+
+## User instance
+```
+systemctl --user enable --now psi-monitor.service psi-alerts.service
+```
 

README.md

@@ -17,6 +17,18 @@ near real time.
 * psi-by-example (a modified version of this is included in this project as a
   submodule)
 * a libnotify-compatible desktop notification system
+    * any notification program should use the `--print-id` parameter if
+      possible
+        * both `notify-send` and `dunstify` (part of
+          [dunst](https://dunst-project.org/)) support this
+    * note, this has only been tested with `dunst`, since it has the capability
+      of showing notification history
+        * `notify-send` specifically does not appear to retain a history, so the
+          `check_dunst_id_is_visible` function won't work with it (and the logic to
+          skip sending a new notification if one is already sent will be broken).  
+            * since I don't use `notify-send`, I'm not sure how to solve this
+            * patches welcome!
+* jq (for the aformentioned `dunst` integration)
 
 ## History
 
@@ -98,6 +110,7 @@ below the configurable threshold for at least five minutes).
     * consider reworking this for a user service, not a system service
         * this could make desktop notifications simpler, and not having to use
           SSH keys without passphrases
+          * possibly learn how to connect to an existing ssh-agent
         * need to become much more familiar with user services
 * consider reworking all code in a compiled language (other than C)
     * time to learn Go

psi-alerts-user.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Pressure Stall Information (PSI) alerts
+PartOf=default.target
+After=psi-monitor.service
+
+[Service]
+Type=simple
+ExecStart=psi-alerts.sh
+
+[Install]
+WantedBy=default.target
+

psi-alerts.sh

@@ -1,8 +1,9 @@
 #!/usr/bin/env zsh
 
+################################################################################
 # Send alerts when Pressure Stall Information is high
 # 
-#    Copyright © 2023 Trey Blancher
+#    Copyright © 2023 Trey Blancher $(base64 -d <<< dHJleUBibGFuY2hlci5uZXQK)
 #
 #    This program is free software: you can redistribute it and/or modify it
 #    under the terms of the GNU General Public License as published by the Free
@@ -16,6 +17,9 @@
 #
 #    You should have received a copy of the GNU General Public License along
 #    with this program.  If not, see <https://www.gnu.org/licenses/>.
+#
+#    Submodules may be distributed under a separate software license;  see the
+#    LICENSE file within each submodule.
 # 
 # This script monitors the systemd journal, specifically the
 # `psi-monitor.service` and waits for Pressure State Information monitor events
@@ -32,12 +36,13 @@
 # systemd psi-alerts@<user>.service overrides (will be placed in
 # /etc/systemd/system/psi-alerts@<user>.service.d/override.conf. See the
 # README.md for details.
-
+################################################################################
 
 svc="psi-monitor.service"
 cpu="/proc/pressure/cpu"
 mem="/proc/pressure/memory"
 io="/proc/pressure/io"
+user="$(whoami)"
 host="$(hostname)"
 email_to="${EMAIL_TO}"
 sms_dst="${SMS_DST}"
@@ -48,25 +53,57 @@ ssh_user="${SSH_USER}"
 ssh_id_path="${SSH_ID_PATH}"
 clear_threshold="${CLEAR_THRESHOLD}"
 notification_cmd="${NOTIFICATION_CMD}"
+notification_hist_cmd="${NOTIFICATION_HIST_CMD}"
 notification_opts="${NOTIFICATION_OPTS}"
 id_idx="${NOTIFICATION_IDX}"
+user=false
 
+if [[ -n "${1}" ]]; then
+    if  [[ "${1}" == "-u" ]] || \
+        [[ "${1}" == "--user" ]]; then
+        user=true
+    fi 
+fi
+       
+get_ssh_agent () {
+    for dir in /tmp/ssh-*; do
+        if [[ -O ${dir} ]]; then
+            # only choose the last agent
+            export SSH_AGENT_PID=$(ps -eaf | grep '[s]sh-agent' | \
+                                   grep ${user} | awk '{print $2}')
+            export SSH_AUTH_SOCK=$(ls ${dir}/agent.* | tail -1)
+        fi
+    done
+
+    if [[ -S ${SSH_AUTH_SOCK} ]]; then
+        # we found an ssh_agent socket
+        true
+    else
+        false
+    fi
+}
 print_psi () {
     local psi_file="${1}"
     cat "${(P)$(tr '[[:upper:]]' '[[:lower:]]' <<< "${psi_file}")}"
 }
 
-print_pidstat () {
+print_stats () {
     local psi_type="${1}"
 
     case "${psi_type}" in
         CPU)
+            top -bcn1 -o %CPU -w 512 | head -n 30
+            printf "\n\n"
             pidstat -ul --human
             ;;
         IO)
+            sudo iotop --batch --only --iter=10
+            printf "\n\n"
             pidstat -dl --human
             ;;
         MEM)
+            top -bcn1 -o %MEM -w 512 | head -n 30
+            printf "\n\n"
             pidstat -rl --human
             ;;
         *)
@@ -97,20 +134,35 @@ send_notice () {
     esac
 
     integer notification_id
-    if ! notification_id=$(ssh -q -i "${ssh_id_path}" "${ssh_user}@${ssh_host}" -p ${ssh_port} \
-        "${notification_cmd} ${notification_opts} '${host}:  PSI ${psi_type} triggered!' '${psi}'"); then
-            print "Connection to notification daemon failed!" >&2
-            false
+    if get_ssh_agent && [[ -S ${SSH_AUTH_SOCK} ]]; then
+        if ! notification_id=$(ssh -q "${ssh_user}@${ssh_host}" -p ${ssh_port} \
+            "${notification_cmd} ${notification_opts} '${host}:  PSI ${psi_type} triggered!' '${psi}'"); then
+                print "Connection to notification daemon failed!" >&2
+                false
+        else
+            print ${notification_id}
+            true
+        fi
+    elif [[ -n "${ssh_id_path}" ]]; then
+        if ! notification_id=$(ssh -q -i "${ssh_id_path}" "${ssh_user}@${ssh_host}" -p ${ssh_port} \
+            "${notification_cmd} ${notification_opts} '${host}:  PSI ${psi_type} triggered!' '${psi}'"); then
+                print "Connection to notification daemon failed!" >&2
+                false
+        else
+            print ${notification_id}
+            true
+        fi
     else
-        echo ${notification_id}
-        true
+        print "No SSH notifications configured.  Returning." >&2
+        false
     fi
     #set +x
 }
 
 send () {
+    #set -x
     if [[ "${#@}" -lt 2 ]] && [[ "${#@}" -gt 3 ]]; then
-        echo "Wrong number of arguments to send()!" >&2
+        print "Wrong number of arguments to send()!" >&2
         return false
     fi
 
@@ -131,45 +183,50 @@ send () {
     local psi="$(print_psi $(tr '[[:upper:]]' '[[:lower:]]' <<< ${psi_type}))"
 
 
-    local email=$(mktemp /tmp/psi.eml.XXXX)
+    local email=$(mktemp /tmp/psi.eml.XXXX.txt)
     local subj
-    printf "Pressure Stall Information triggered on ${psi_type} at $(date +'%FT%T %Z')\n\n" > ${email}
+    printf "Pressure Stall Information for ${host} triggered on ${psi_type} at $(date +'%FT%T %Z')\n\n" > ${email}
     if [[ -n "${current_alarms}" ]]; then
-        subj="PSI on deltachunk ${current_alarms} triggered!"
+        current_alarms="${current_alarms}|${psi_type}"
+        subj="PSI on ${host} ${current_alarms} triggered!"
         printf "Multiple alarms triggered:  ${current_alarms}\n\n" >> ${email}
     else
-        subj="PSI on deltachunk ${psi_type} triggered!"
+        subj="PSI on ${host} ${psi_type} triggered!"
         current_alarms="${psi_type}"
     fi
-
+    print_psi "${psi_type}" >> ${email}
+    printf "\n\n" >> ${email}
     # is this an email or SMS?
-    if [[ ! "${dst}" =~ "${sms_domain}" ]]; then
+    if [[ ! "${dst}" =~ "@${sms_domain}" ]]; then
         for p in $(tr '|' ' ' <<< "${current_alarms}"); do
-            printf "\npidstat info for ${p}\n\n" >> ${email}
-            print_pidstat "${p}" >> ${email}
+            printf "\n\nStatistics info for ${p}\n\n" >> ${email}
+            print_stats "${p}" >> ${email}
             printf "\n\n" >> ${email}
         done
     fi
 
     # send the message
-    /usr/bin/mail --resource-files=/ \
-                  --subject="${subj}" \
-                  --end-options \
-                  ${dst} < ${email}
+    (
+       printf "To:  ${dst}\n"
+       printf "Subject:  ${subj}\n"
+       cat ${email}
+    ) | sendmail -t
+         
+    #set +x
 }
 
 is_clear () {
     local psi_type="${1}"
     local psi_file="$(tr '[[:upper:]]' '[[:lower:]]' <<< "${psi_type}")"
 
-    local avg10=$(grep some "${(P)psi_file}" | awk '{print $2}' | awk -F= '{print $2}')
+    local avg300=$(grep some "${(P)psi_file}" | awk '{print $4}' | awk -F= '{print $2}')
     local prev=$(grep some "${(P)psi_file}" | awk '{print $5}' | awk -F= '{print $2}')
 
     
-    if [[ ${avg10} -lt ${clear_threshold} ]]; then
-        return 0
+    if [[ ${avg300} -lt ${clear_threshold} ]]; then
+        true
     else
-        return 1
+        false
     fi
 }
 
@@ -187,7 +244,7 @@ exec_notices () {
                 send "${psi_type}" "${current_alarms}" "${email_to}"
                 ;;
             *)
-                echo "Something went wrong!" >&2
+                print "Something went wrong!" >&2
                 false
                 ;;
         esac
@@ -204,56 +261,83 @@ check_dunst_id_is_visible () {
     local dunst_id="${1}"
 
     typeset -a ids
-    if ids=$(ssh -q "${ssh_host}" -p ${ssh_port} \
-        "dunstctl history | jq '.data[0][][${id_idx}].data'"); then
-            echo "Connection to dunst failed!" >&2
-            return 2
+    if ! ids=$(ssh -q "${ssh_host}" -p ${ssh_port} -l "${ssh_user}" \
+        "${notification_hist_cmd} | jq '.data[0][].id.data'"); then
+        if ! ids=$(ssh -qi "${ssh_id_path}" -p ${ssh_port} -l "${ssh_user}" \
+            "${ssh_host}" "${notification_hist_cmd} | jq '.data[0][].id.data'"); then
+                print "Connection to dunst failed!" >&2
+                return 2
+        fi
     fi
 
+    # if the alert is visible, it's not in the dunst history
     if grep -qP "\b${dunst_id}\b" <<< "${ids}"; then
-        true
-    else
         false
+    else
+        true
     fi
 }
-#set -x
+
 local current_alarm=""
-local last_alarm=""
 typeset -A notice_sent
 typeset -A secs
 integer last_dunst_id=-1
+local last_line=""
 
-journalctl -b 0 -fu "${svc}"  | \
-while read line; do
-    local psi_type="$(grep -Eo "(CPU|MEM|IO) PSI event" <<< "${line}" | grep -Eo "CPU|MEM|IO")"
-    if [[ -n "${psi_type}" ]]; then
-        secs+=(${psi_type} $(date +%s))
-        if [[ "${psi_type}" != "${last_alarm}" ]]; then
+#set -x
+while true; do
+    if ${user}; then
+        line=$(journalctl --user -u ${svc} -n1)
+    else
+        line=$(journalctl -u ${svc} -n1)
+    fi
+    now=$(date +%s)
+    last_timestamp=$(date -d "$(awk '{print $1" "$2" "$3}' <<< "${line}")" +%s)
+    time_diff=$(( now - last_timestamp ))
+    if [[ "${last_line}" == "${line}" ]]; then
+        # last line hasn't changed, check to see if we can clear alarms
+        if (( time_diff >= 3 )); then
+            # haven't seen a monitor alert for 3 seconds, see if we can clear them
+            if [[ -n "${current_alarms}" ]]; then
+                typeset -a alarms=( $(tr '|' ' ' <<< "$current_alarms") )
+                for alarm in ${alarms}; do
+                    integer elapsed=$(( now - ${secs[${alarm}]} ))
+                    if is_clear "${alarm}" && (( elapsed >= 300 )); then
+                        current_alarms=$(sed -E "s/${alarm}\|?//; s/|$//" <<< "${current_alarms}")
+                        unset "notice_sent[${alarm}]"
+                        unset "secs[${alarm}]"
+                    fi
+                done
+            fi
+            sleep 1
+            continue
+        fi
+    
+        sleep 1
+        continue
+    fi
+    last_line="${line}"
+    if (( time_diff < 3 )); then
+        local psi_type="$(grep -Eo "(CPU|MEM|IO) PSI event" <<< "${line}" | grep -Eo "CPU|MEM|IO")"
+        if [[ -n "${psi_type}" ]]; then
+            secs+=(${psi_type} ${now})
             if [[ ! ${notice_sent[${psi_type}]} ]]; then
                 last_dunst_id=$(exec_notices "${psi_type}" "${current_alarms}")
                 notice_sent+=(${psi_type} true)
-            elif (( last_dunst_id >= 0 )) && ! check_dunst_id_is_visible "${last_dunst_id}"; then
+            elif (( last_dunst_id >= 0 )) && check_dunst_id_is_visible "${last_dunst_id}"; then
+                sleep 1
                 continue
             fi
-        fi
-        last_alarm="${psi_type}"
-        if [[ -z "${current_alarms}" ]]; then
-            current_alarms="${psi_type}"
-        else
-            if ! grep -q "${psi_type}" <<< "${current_alarms}"; then
-                current_alarms="${current_alarms}|${psi_type}"
+            if [[ -z "${current_alarms}" ]]; then
+                current_alarms="${psi_type}"
+            else
+                if ! grep -q "${psi_type}" <<< "${current_alarms}"; then
+                    current_alarms="${current_alarms}|${psi_type}"
+                fi
             fi
         fi
-    else
-        typeset -a alarms=( $(tr '|' ' ' <<< "$current_alarms") )
-        for alarm in ${alarms}; do
-            integer elapsed=$(( $(date +%s) - ${secs[${alarm}]} ))
-            if is_clear "${alarm}" && (( elapsed > 300 )); then
-                current_alarms=$(sed -E "s/${alarm}\|?//" <<< "${current_alarms}")
-                last_alarm=$(awk -F'|' '{print $NF}' <<< "${current_alarms}")
-            fi
-        done
     fi
+    sleep 1
 done
 #set +x
 

psi-monitor-user.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Pressure Stall Information (PSI) Monitor
+PartOf=default.target
+
+[Service]
+Type=simple
+ExecStart=/home/trey/bin/psi-monitor.sh 80
+
+[Install]
+WantedBy=default.target

psi-monitor.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env zsh
+#
+# Pressure Stall Information monitor
+#
+#    Copyright © 2023 Trey Blancher $(base64 -d <<< dHJleUBibGFuY2hlci5uZXQK)
+#
+#    This program is free software: you can redistribute it and/or modify it
+#    under the terms of the GNU General Public License as published by the Free
+#    Software Foundation, either version 3 of the License, or (at your option)
+#    any later version.
+#
+#    This program is distributed in the hope that it will be useful, but
+#    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+#    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+#    for more details.
+#
+#    You should have received a copy of the GNU General Public License along
+#    with this program.  If not, see <https://www.gnu.org/licenses/>.
+#
+#    Submodules may be distributed under a separate software license;  see the
+#    LICENSE file within each submodule.
+# 
+# This script monitors the three pressure stall information files
+# /proc/pressure{cpu,io,memory} and reports if any resource is above threshold
+# for the "some" values.  It takes an optional single argument, the threshold at
+# which to alert.  If this is not supplied, it defaults to a threshold of 30.0 
+# percent.
+#
+
+local cpu="/proc/pressure/cpu"
+local cpu_ctr=0
+local io="/proc/pressure/io"
+local io_ctr=0
+local mem="/proc/pressure/memory"
+local mem_ctr=0
+local threshold=30.0
+
+if [[ -n "${1}" ]]; then
+    threshold=${1}
+fi
+
+# main loop
+while true; do
+    local cpu_pct=$(grep 'some' ${cpu} | awk '{print $2}' | awk -F'=' '{print $2}')    
+    local io_pct=$(grep 'some' ${io} | awk '{print $2}' | awk -F'=' '{print $2}')    
+    local mem_pct=$(grep 'some' ${mem} | awk '{print $2}' | awk -F'=' '{print $2}')    
+    
+    if (( cpu_pct > threshold )); then
+        cpu_ctr=$(( ${cpu_ctr} + 1 ))
+        printf "CPU PSI event %d triggered.\n" ${cpu_ctr}
+    fi
+    if (( io_pct > threshold )); then
+        io_ctr=$(( ${io_ctr} + 1 ))
+        printf "IO PSI event %d triggered.\n" ${io_ctr}
+    fi
+    if (( mem_pct > threshold )); then
+        mem_ctr=$(( ${mem_ctr} + 1 ))
+        printf "MEM PSI event %d triggered.\n" ${mem_ctr}
+    fi
+
+    sleep 10
+done