strace_apache_speed []

This is an old revision of the document!

Only works with NON https Website!!!!
Only works with apache

screen -S telnet

$ telnet localhost 80
GET / HTTP/1.1 
Host: example.com

*Press ENTER Once*
“Ctrl-a” *New Screen Session*

screen -S strace

lsof -p `pidof telnet`

netstat -nap | grep PID

strace -o /tmp/output -f -r -s4096 -p 16742

"Ctrl-a"

Flag	Description
o	ouput file
f	Trace child processes as they are created by currently traced processes as a result of the fork(2) system call
r	Print a relative timestamp upon entry to each system call. This records the time difference between the beginning of successive system calls
p	PID
s	string size (IMPORTANT - strings are truncated by default, sometimes you need to see larger string size to analyse correctly

—————————-

*go back to telnet and press enter twice * * wait for http response * “Ctrl-a”

* go back to screen session with strace and close once http response etc)*

cat /tmp/output | cut -c12-16 | sort -rn | head