A deeper understanding of the underlying active processes in CentOS 7 is an essential skill for any troubleshooter. From high load averages to slow response times, system overloads to dead and dying processes, there comes a time when every server may start to feel sluggish, act impoverished, or fail to respond, and as a consequence, it will require your immediate attention.
In this chapter, we will:
Learn about memory management, swap, swappiness, and thrashing
Learn how to analyze active processes using the
vmstat,top, andpscommandsLearn how to monitor the server with
iotop,iostat, andlsofLearn about system load and
systemdLearn how to find process IDs, identify parent process IDs and orphaned processes, and initiate the various forms of the
killsignal