Number of process on Linux system

The number of active processes on a Linux system can be filled into an RRD database with this script. This script works as it is stored (and executable) under /var/www/rrd/processes

#!/bin/bash

cd /var/www/rrd

# create database if not exists
[ -f processes.rrd ] || {
/usr/bin/rrdtool create processes.rrd --step 300 \
DS:processes:GAUGE:1200:U:U \
RRA:AVERAGE:0.5:1:3200 \
RRA:AVERAGE:0.5:6:3200 \
RRA:AVERAGE:0.5:36:3200 \
RRA:AVERAGE:0.5:144:3200 \
RRA:AVERAGE:0.5:1008:3200 \
RRA:AVERAGE:0.5:4320:3200 \
RRA:AVERAGE:0.5:52560:3200 \
RRA:AVERAGE:0.5:525600:3200
}

# Use ps and wc to determine the number of processes
PROZESSE=$(ps hax|wc -l)

# Finally, the data comes into the database
# N stands for the current date and time
/usr/bin/rrdtool update processes.rrd N:$PROZESSE

The following line must be added in /etc/crontab to call the script every 5 minutes:

*/5 *   * * *   root    /var/www/rrd/processes