Strace
= STRACE - Traces System Calls and Signals =
Strace is used for debugging process etc. which may be causing high CPU usage etc. which may be identified using “top” and/or “ps -eaf” etc.
Problem: A particular process is eating/using up CPU time. There are no logs from the process/program itself and you need to find out what is causing the bottleneck/problem.
Step 1: Find the PID (process id) ps -eaf | grep process // or pgrep process
Step 2: Run strace and attach to process. strace -fp processID // f = trace child processes as they are forked // p = attach to processID
strace -fp processID -o outputfile
strace -fp processID -o outputfile -r // appends a timestamp to each line of output.
I hope you solve your problem. Issues you may find → Files not existing, Cannot read/write to files. Repeated connection attempts by users etc.
More info at: http://www.debian-administration.org/articles/352