Linux Performance Analysis in 60k Milliseconds (2015) [pdf](brendangregg.com)
brendangregg.com
Linux Performance Analysis in 60k Milliseconds (2015) [pdf]
https://www.brendangregg.com/Articles/Netflix_Linux_Perf_Analysis_60s.pdf
https://www.brendangregg.com/Articles/Netflix_Linux_Perf_Analysis_60s.pdf
For me, it's the very first thing I'll run (e.g., `strace -p PID`) if a any process is not performing well enough.
It gives a quick insight on what syscalls it's making.