#!/usr/bin/perl -w

# put this in snmpd.conf:
# exec .1.3.6.1.4.1.X.Y cpu /path/to/this/script.pl
#
# X and Y are numbers of your choosing I suppose. I'm still a little new
# to snmp. I keep X the same across all my stuff and Y is unique per 
# service that I'm providing.
# you can then 'snmpget hostname .1.3.6.1.4.1.X.Y.101.1'
# and will get back something like: u:32,s:15,i:53

use strict;

# line by line vmstat output for 2 iterations.
# mine looks like:
# procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
#  r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy id wa
#  0  0  29708  72468  39012 272552    0    0    15    22   12    15  1  0 97  1
#  0  0  29708  72340  39012 272680    0    0    64     0 1092   205  0  0 100  0
my @lines = split /\n/,`vmstat 2 2`;

# $lines[1] is our column headers, trim of the leading whitespace
# then split them out to an array
$lines[1] =~ s/^\s+//;
my @head = split /\s+/, $lines[1];

# The last line is the one with useful data. Trim it and split it too.
$lines[$#lines] =~ s/^\s+//;
my @data = split /\s+/, $lines[$#lines];

# match the headers and data into a hash
my %data;
for my $x (0 .. $#data)
{
	$data{$head[$x]} = $data[$x];
}

print STDOUT "u:${data{'us'}},s:${data{'sy'}},i:${data{'id'}}\n";
exit 0;