Performance "problems" come in many flavors. Here we begin capturing real-life problem determination examples and techniques, showing how easy it can be to drive towards understanding and fixing the root-cause issues, or in many cases simply to better understand the performance comparisons being made.

Contents

Gathering basic performance data

For details on the initial data to consider, see gathering basic performance data .

Who's doing a "stat" on a file?

See Using SystemTap for stat for an example of looking for which process is stat'ing a file.

Who's sending so many SIGUSR2 signals?

See SystemTap SIGUSR2 Tracing. This page explains how to easily determine the source of software-generated signals, which in this example were causing a system to become 100% CPU busy.