CPU

Some useful links to explain the concepts of CPU processing

Concepts

• https://www.slashroot.in/difference-between-process-and-thread-linux

• http://blog.scoutapp.com/articles/2009/07/31/understanding-load-averages

Types of Processes

• http://www.gmarik.info/blog/2012/orphan-vs-zombie-vs-daemon-processes/

Output of ps command - Explained

• http://superuser.com/questions/117913/ps-aux-output-meaning

• http://thelinuxstuff.blogspot.in/2012/08/process-state-codes-in-ps-output.html

Commands

NoHUP &

• https://stackoverflow.com/questions/15595374/whats-the-difference-between-nohup-and-ampersand

• https://unix.stackexchange.com/questions/3886/difference-between-nohup-disown-and

top

• http://www.thegeekstuff.com/2010/01/15-practical-unix-linux-top-command-examples/

• http://www.slashroot.in/linux-cpu-performance-monitoring-tutorial

• http://www.tecmint.com/command-line-tools-to-monitor-linux-performance/

• http://tecadmin.net/understanding-linux-top-command-results-uses/

• http://linuxaria.com/howto/understanding-the-top-command-on-linux

• http://www.tecmint.com/12-top-command-examples-in-linux/

• http://linoxide.com/linux-command/linux-top-command-examples-screenshots/

• http://www.dowdandassociates.com/blog/content/howto-troubleshoot-with-linux-top-command/

• http://www.linuxjournal.com/magazine/hack-and-linux-troubleshooting-part-i-high-load

• http://www.crucialp.com/resources/tutorials/server-administration/server-loads-explained-linux-unix/

• https://haydenjames.io/use-atop-linux-server-performance-analysis/

• https://alvinalexander.com/linux/unix-linux-process-memory-sort-ps-command-cpu

• https://math-linux.com/linux/tip-of-the-day/article/find-out-biggest-cpu-memory-consuming-processes-with-ps-command

SAR

• http://www.thegeekstuff.com/2011/03/sar-examples/

• http://linoxide.com/linux-command/linux-system-performance-monitoring-using-sar-command/

• http://www.slashroot.in/examples-using-sar-command-system-monitoring-linux

• http://www.blackmoreops.com/2014/06/18/sysstat-sar-examples-usage/

• http://linoxide.com/linux-command/linux-pidstat-monitor-statistics-procesess/

• http://www.thegeekstuff.com/2014/11/pidstat-examples/

• http://www.yourownlinux.com/2014/08/sar-command-in-linux-tutorial-with-examples.html

• https://crybit.com/sar-command/

• http://www.cyberciti.biz/open-source/command-line-hacks/linux-monitor-process-using-pidstat/

Nice / Renice / IOnice

• https://www.faqforge.com/linux/reduce-load-of-backup-scripts-with-nice-and-ionice/

• http://www.slashroot.in/nice-and-renice-command-usage-examples-process-priority-linux

KILL

• http://www.thegeekstuff.com/2012/03/linux-signals-fundamentals/

• https://www.quora.com/What-is-the-difference-between-Kill-and-Kill-9-command-in-Unix

• http://bencane.com/2014/04/01/understanding-the-kill-command-and-how-to-terminate-processes-in-linux/

• https://rtcamp.com/tutorials/linux/kill-all-processes/

• http://www.tecmint.com/how-to-kill-a-process-in-linux/

• https://www.digitalocean.com/community/tutorials/how-to-use-ps-kill-and-nice-to-manage-processes-in-linux

• http://www.cyberciti.biz/faq/unix-linux-killall-command-examples-usage-syntax/

• https://unix.stackexchange.com/questions/252349/what-is-the-difference-between-kill-pkill-and-killall

HTop

Visual representation of all HTop parameters

• https://codeahoy.com/2017/01/20/hhtop-explained-visually/

HTop command - Explained

• https://peteris.rocks/blog/htop/

• http://www.servercraftmen.com/performance-tuning-htop-usage/

• http://www.webhostingbuzz.com/wiki/install-htop-linux/

• https://www.tecmint.com/install-htop-linux-process-monitoring-for-rhel-centos-fedora/

• https://delightlylinux.wordpress.com/2014/03/24/htop-a-better-process-viewer-then-top/

• http://www.thegeekstuff.com/2011/09/linux-htop-examples

SysDig

• https://sysdig.com/blog/sysdig-vs-dtrace-vs-strace-a-technical-discussion/

• https://www.sysdig.org/wiki/sysdig-user-guide/

• https://github.com/draios/sysdig/wiki/Sysdig-Examples

• https://sysdig.com/blog/linux-troubleshooting-cheatsheet/

• http://bencane.com/2014/04/18/using-sysdig-to-troubleshoot-like-a-boss/

• http://xmodulo.com/monitor-troubleshoot-linux-server-sysdig.html

Configuration

Troubleshooting & Log Parsing

• Find the most number of processes running on the system

sudo ps -AL --no-headers | awk -F: '{print $3}' | cut -d' ' -f2 | sort | uniq -c | sort -n | tail -10

• Check for zombie processes with PPID

sudo ps axo stat,ppid,pid,comm | grep -w defunct

• View Column Headers in ps output

sudo ps aux | head -1 && sudo ps aux | grep <process-name> | grep -v grep