-=head1 NAME
+=head1 NAME
rrd-beginners - RRDtool Beginners' Guide
RRDtool is designed to store time series of data. With every data
update, an assosiated time stamp is stored. Time is always expressed
-in seconds passed since epoch (01-01-1971). RRDtool can be installed
+in seconds passed since epoch (01-01-1970). RRDtool can be installed
on Unix as well as Windows. It comes with a command set to carry out
various operations on RRD databases. This command set can be accessed
from the command line, as well as from Shell or Perl scripts. The
Values = 300, 600, 900, 1200
Step = 300 seconds
- COUNTER DS = 1, 1, 1, 1
+ COUNTER DS = 1, 1, 1, 1
DERIVE DS = 1, 1, 1, 1
- ABSOLUTE DS = 1, 2, 3, 4
+ ABSOLUTE DS = 1, 2, 3, 4
GAUGE DS = 300, 600, 900, 1200
The next parameter is B<heartbeat>. In our example, heartbeat is 600
=head3 Perl script (retrieves data from database and generates graphs and statistics)
#!/usr/bin/perl -w
- # This script fetches data from target.rrd, creates a graph of memory
+ # This script fetches data from target.rrd, creates a graph of memory
# consumption on the target (Dual P3 Processor 1 GHz, 656 MB RAM)
# call the RRD perl module
my $start_time = $end_time - 2592000; # set start 30 days in the past
# fetch average values from the RRD database between start and end time
- my ($start,$step,$ds_names,$data) =
- RRDs::fetch("target.rrd", "AVERAGE",
+ my ($start,$step,$ds_names,$data) =
+ RRDs::fetch("target.rrd", "AVERAGE",
"-r", "600", "-s", "$start_time", "-e", "$end_time");
# save fetched values in a 2-dimensional array
my $rows = 0;