Tells you the average size of your Apache processes

avg-apache-process.sh

#!/bin/bash
#
# Tells you the average size of your Apache processes

# It must run on a live apache server (unless you know what you are doing).
# It requires pmap, /proc, ps, grep, awk, sed and bc,
#
# Written by: Amr Mostafa" <[email protected]>
#
# Courtesy of Egypt Development Centre (c).
# Licensed under GPL v3 or later.
#
# =| USAGE |===================================================================
#
#   echo <parent-apache-process-id> | avg-apache-process.sh
#
# In Debian systems, that translates to:
#
#   cat /var/run/apache2.pid | max-clients.sh
#
# In RedHat systems, that translates to:
#
#   cat /var/run/httpd.pid | max-clients.sh
#
# Enjoy!

if [ ! "$UID" -eq "0" ]
then echo "WARNING: This should be run as root." >&2; fi
 
read APACHE_PID
MEM_TOTAL=$(cat /proc/meminfo | awk '/MemTotal/ {print $2}')
 
# Before someone WTFs the next ps line..
# h: omit header
# opid: only print 'pid' column.
# ppid: print only processes whose parent process' id equal to given pid.
HTTPD_AVG_MEM=$(ps --ppid $APACHE_PID h opid |
# Use pmap to retrieve process memory consumption
while read pid; do
  pmap -d $pid |
  tail -n1 |
  sed 's/.*private: \([0-9]*\).*/\1/';
done |
# Get average
awk '{ SUM += $1 } END {print SUM/NR}')
 
echo "scale=2; $HTTPD_AVG_MEM / 1024" | bc