From 5e259f7616b0050f2933fc191dee26d660c474d2 Mon Sep 17 00:00:00 2001 From: DarkSun Date: Fri, 21 Jun 2019 17:20:46 +0800 Subject: [PATCH] =?UTF-8?q?=E9=80=89=E9=A2=98:=2020190621=20Bash=20Script?= =?UTF-8?q?=20to=20Monitor=20Memory=20Usage=20on=20Linux?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sources/tech/20190621 Bash Script to Monitor Memory Usage on Linux.md --- ...Script to Monitor Memory Usage on Linux.md | 175 ++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 sources/tech/20190621 Bash Script to Monitor Memory Usage on Linux.md diff --git a/sources/tech/20190621 Bash Script to Monitor Memory Usage on Linux.md b/sources/tech/20190621 Bash Script to Monitor Memory Usage on Linux.md new file mode 100644 index 0000000000..ded8050ee7 --- /dev/null +++ b/sources/tech/20190621 Bash Script to Monitor Memory Usage on Linux.md @@ -0,0 +1,175 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Bash Script to Monitor Memory Usage on Linux) +[#]: via: (https://www.2daygeek.com/linux-bash-script-to-monitor-memory-utilization-usage-and-send-email/) +[#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/) + +Bash Script to Monitor Memory Usage on Linux +====== + +There are many open source monitoring tools are currently available in market to monitor Linux systems performance. + +It will send an email alert when the system reaches the specified threshold limit. + +It monitors everything such as CPU utilization, Memory utilization, swap utilization, disk space utilization and much more. + +If you only have few systems and want to monitor them then writing a small shell script can make your task very easy. + +In this tutorial we have added two shell script to monitor Memory utilization on Linux system. + +When the system reaches the given threshold then it will trigger a mail to given email id. + +### Method-1 : Linux Bash Script To Monitor Memory Utilization And Send an Email + +If you want to only get current Memory utilization percentage through mail when the system reaches the given threshold, use the following script. + +This is very simple, straightforward and one line script. I preferred to go with this method in most of the time. + +It will trigger an email when your system reaches `80%` of Memory utilization. + +``` +*/5 * * * * /usr/bin/free | awk '/Mem/{printf("RAM Usage: %.2f%\n"), $3/$2*100}' | awk '{print $3}' | awk '{ if($1 > 80) print $0;}' | mail -s "High Memory Alert" [email protected] +``` + +**Note:** You need to change the email id instead of ours. Also, you can change the Memory utilization threshold value as per your requirement. + +**Output:** You will be getting an email alert similar to below. + +``` +High Memory Alert: 80.40% +``` + +We had added many useful shell scripts in the past. If you want to check those, navigate to the below link. + + * **[How to automate day to day activities using shell scripts?][1]** + + + +### Method-2 : Linux Bash Script To Monitor Memory Utilization And Send an Email + +If you want to get more information about the Memory utilization in the mail alert. + +Then use the following script, which includes top Memory utilization process details based on the top Command and ps Command. + +This will instantly gives you an idea what is going on your system. + +It will trigger an email when your system reaches `80%` of Memory utilization. + +**Note:** You need to change the email id instead of ours. Also, you can change the Memory utilization threshold value as per your requirement. + +``` +# vi /opt/scripts/memory-alert.sh + +#!/bin/sh +ramusage=$(free | awk '/Mem/{printf("RAM Usage: %.2f\n"), $3/$2*100}'| awk '{print $3}') + +if [ "$ramusage" > 20 ]; then + +SUBJECT="ATTENTION: Memory Utilization is High on $(hostname) at $(date)" + +MESSAGE="/tmp/Mail.out" + +TO="[email protected]" + + echo "Memory Current Usage is: $ramusage%" >> $MESSAGE + + echo "" >> $MESSAGE + + echo "------------------------------------------------------------------" >> $MESSAGE + + echo "Top Memory Consuming Process Using top command" >> $MESSAGE + + echo "------------------------------------------------------------------" >> $MESSAGE + + echo "$(top -b -o +%MEM | head -n 20)" >> $MESSAGE + + echo "" >> $MESSAGE + + echo "------------------------------------------------------------------" >> $MESSAGE + + echo "Top Memory Consuming Process Using ps command" >> $MESSAGE + + echo "------------------------------------------------------------------" >> $MESSAGE + + echo "$(ps -eo pid,ppid,%mem,%Memory,cmd --sort=-%mem | head)" >> $MESSAGE + + mail -s "$SUBJECT" "$TO" < $MESSAGE + + rm /tmp/Mail.out + + fi +``` + +Finally add a **[cronjob][2]** to automate this. It will run every 5 minutes. + +``` +# crontab -e +*/5 * * * * /bin/bash /opt/scripts/memory-alert.sh +``` + +**Note:** You will be getting an email alert 5 mins later since the script has scheduled to run every 5 minutes (But it’s not exactly 5 mins and it depends the timing). + +Say for example. If your system reaches the given limit at 8.25 then you will be getting an email alert in another 5 mins. Hope it’s clear now. + +**Output:** You will be getting an email alert similar to below. + +``` +Memory Current Usage is: 80.71% + ++------------------------------------------------------------------+ +Top Memory Consuming Process Using top command ++------------------------------------------------------------------+ +top - 12:00:58 up 5 days, 9:03, 1 user, load average: 1.82, 2.60, 2.83 +Tasks: 314 total, 1 running, 313 sleeping, 0 stopped, 0 zombie +%Cpu0 : 8.3 us, 12.5 sy, 0.0 ni, 75.0 id, 0.0 wa, 0.0 hi, 4.2 si, 0.0 st +%Cpu1 : 13.6 us, 4.5 sy, 0.0 ni, 81.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +%Cpu2 : 21.7 us, 21.7 sy, 0.0 ni, 56.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +%Cpu3 : 13.6 us, 9.1 sy, 0.0 ni, 77.3 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +%Cpu4 : 17.4 us, 8.7 sy, 0.0 ni, 73.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +%Cpu5 : 20.8 us, 4.2 sy, 0.0 ni, 70.8 id, 0.0 wa, 0.0 hi, 4.2 si, 0.0 st +%Cpu6 : 9.1 us, 0.0 sy, 0.0 ni, 90.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +%Cpu7 : 17.4 us, 4.3 sy, 0.0 ni, 78.3 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st +KiB Mem : 16248588 total, 5015964 free, 6453404 used, 4779220 buff/cache +KiB Swap: 17873388 total, 16928620 free, 944768 used. 6423008 avail Mem + + PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND +17163 daygeek 20 2033204 487736 282888 S 10.0 3.0 8:26.07 /usr/lib/firefox/firefox -contentproc -childID 15 -isForBrowser -prefsLen 9408 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /u+ + 1121 daygeek 20 4191388 419180 100552 S 5.0 2.6 126:02.84 /usr/bin/gnome-shell + 1902 daygeek 20 1701644 327216 82536 S 20.0 2.0 153:27.92 /opt/google/chrome/chrome + 2969 daygeek 20 1051116 324656 92388 S 15.0 2.0 149:38.09 /opt/google/chrome/chrome --type=renderer --field-trial-handle=10346122902703263820,11905758137655502112,131072 --service-pipe-token=1339861+ + 1068 daygeek 20 1104856 309552 278072 S 5.0 1.9 143:47.42 /usr/lib/Xorg vt2 -displayfd 3 -auth /run/user/1000/gdm/Xauthority -nolisten tcp -background none -noreset -keeptty -verbose 3 +27246 daygeek 20 907344 265600 108276 S 30.0 1.6 10:42.80 /opt/google/chrome/chrome --type=renderer --field-trial-handle=10346122902703263820,11905758137655502112,131072 --service-pipe-token=8587368+ + ++------------------------------------------------------------------+ +Top Memory Consuming Process Using ps command ++------------------------------------------------------------------+ + PID PPID %MEM %CPU CMD + 8223 1 6.4 6.8 /usr/lib/firefox/firefox --new-window +13948 1121 6.3 1.2 /usr/bin/../lib/notepadqq/notepadqq-bin + 8671 8223 4.4 7.5 /usr/lib/firefox/firefox -contentproc -childID 5 -isForBrowser -prefsLen 6999 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab +17163 8223 3.0 0.6 /usr/lib/firefox/firefox -contentproc -childID 15 -isForBrowser -prefsLen 9408 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab + 1121 1078 2.5 1.6 /usr/bin/gnome-shell +17937 8223 2.5 0.8 /usr/lib/firefox/firefox -contentproc -childID 16 -isForBrowser -prefsLen 9410 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab + 8499 8223 2.2 0.6 /usr/lib/firefox/firefox -contentproc -childID 4 -isForBrowser -prefsLen 6635 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab + 8306 8223 2.2 0.8 /usr/lib/firefox/firefox -contentproc -childID 1 -isForBrowser -prefsLen 1 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab + 9198 8223 2.1 0.6 /usr/lib/firefox/firefox -contentproc -childID 7 -isForBrowser -prefsLen 8604 -prefMapSize 184979 -parentBuildID 20190521202118 -greomni /usr/lib/firefox/omni.ja -appomni /usr/lib/firefox/browser/omni.ja -appdir /usr/lib/firefox/browser 8223 true tab +``` + +-------------------------------------------------------------------------------- + +via: https://www.2daygeek.com/linux-bash-script-to-monitor-memory-utilization-usage-and-send-email/ + +作者：[Magesh Maruthamuthu][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://www.2daygeek.com/author/magesh/ +[b]: https://github.com/lujun9972 +[1]: https://www.2daygeek.com/category/shell-script/ +[2]: https://www.2daygeek.com/crontab-cronjob-to-schedule-jobs-in-linux/