atop - useful tool for investigation and incident RCA on Linux
Atop is an ASCII full-screen performance monitor for Linux that is capable of reporting the activity of all processes (even if processes have finished during the interval), daily logging of system and process activity for long-term analysis, highlighting overloaded system resources by using colors, etc. At regular intervals, it shows system-level activity related to the CPU, memory, swap, disks (including LVM) and network layers, and for every process (and thread) it shows e.g. the CPU utilization, memory growth, disk utilization, priority, username, state, and exit code. In combination with the optional kernel module netatop , it even shows network activity per process/thread. The command atop has some major advantages compared to other performance monitoring tools: Resource consumption by all processes It shows the resource consumption by all processes that were active during the interval, so also the resource consumption by those process