我是 Perl 和 RRD 的新手。
我试图实现一个简单的例子,虽然看起来运行正常,但没有显示输出。图片正常生成,但图中没有数据。
我一直在遵循 CPAN 文档进行实施RRD::Simple
,理论上我做错了。我尝试调试代码,看起来不错,但是在打印图表时没有数据。
#!/usr/bin/perl
use strict;
use warnings;
use RRD::Simple ();
use Data::Dumper;
$| = 1; # Flush the output
my ($rrd, $unixtime, $file);
$file = "perl.txt";
my $path = '/home/os/Desktop/Test_Perl/';
my $period = '3years';
my $rrdfile = 'myfile.rrd';
while (sleep 15) {
open(FH, ">>", $file) || die "Unable to open $file: $!\n";
my $range = 50;
my $minimum = 100;
my $random_number_in = int(rand($range)) + $minimum;
my $random_number_out = int(rand($range)) + $minimum;
my $random_number_sec = int(rand($range)) + $minimum;
# Create an interface object
$rrd = RRD::Simple->new(
file => $rrdfile,
cf => [qw( AVERAGE MIN MAX LAST )],
#default_dstype => "DERIVE",
);
unless (-e $rrdfile) {
# Create a new RRD file with 3 data sources called
# bytesIn, bytesOut and faultsPerSec.
$rrd->create(
$period,
step => 5, # 5 sec interval
bytesIn => "GAUGE",
bytesOut => "GAUGE",
faultsPerSec => "GAUGE"
);
}
# Put some arbitary data values in the RRD file for the same
# 3 data sources called bytesIn, bytesOut and faultsPerSec.
$rrd->update(
bytesIn => $random_number_in,
bytesOut => $random_number_out,
faultsPerSec => $random_number_sec
);
print FH "This is the bytes_in: $random_number_in\n";
print FH "This is the bytes_out: $random_number_out\n";
print FH "This is the bytes_sec: $random_number_sec\n";
# Generate graphs:
# /home/os/Desktop/Test_Perl/myfile-hourly.png, /home/os/Desktop/Test_Perl/myfile-daily.png
# /home/os/Desktop/Test_Perl/myfile-weekly.png, /home/os/Desktop/Test_Perl/myfile-monthly.png
my %rtn = $rrd->graph(
$rrdfile,
destination => $path,
basename => "my_graph",
timestamp => "both", # graph, rrd, both or none
periods => [qw(hour day week month)], # omit to generate all graphs
sources => [qw(bytesIn bytesOut faultsPerSec)],
source_colors => [qw(ff0000 aa3333 000000)],
source_labels => [("Bytes In", "Bytes Out", "Faults Per Second")],
source_drawtypes => [qw(LINE1 AREA LINE)],
line_thickness => 2,
extended_legend => 1,
title => "Network Interface eth0",
vertical_label => "Bytes/Faults",
width => 800,
height => 500,
interlaced => "", # If images are interlaced they become visible to browsers more quickly
);
printf("Created %s\n", join(", ", map { $rtn{$_}->[0] } keys %rtn));
# Return information about an RRD file
my $info = $rrd->info($rrdfile); # This method will return a complex data structure containing details about the RRD file, including RRA and data source information.
print Data::Dumper::Dumper($info);
my @sources = $rrd->sources($rrdfile);
my $seconds = $rrd->retention_period($rrdfile); # This method will return the maximum period of time (in seconds) that the RRD file will store data for.
# Get unixtime of when RRD file was last updated
$unixtime = $rrd->last($rrdfile);
print FH "myfile.rrd was last updated at " . scalar(localtime($unixtime)) . "\n";
# Get list of data source names from an RRD file
my @dsnames = $rrd->sources;
print "Available data sources: " . join(", ", @dsnames) . "\n";
my $heartbeat_In = $rrd->heartbeat($rrdfile, "bytesIn");
my $heartbeat_Out = $rrd->heartbeat($rrdfile, "bytesOut");
my $heartbeat_sec = $rrd->heartbeat($rrdfile, "faultsPerSec"); # This method will return the current heartbeat of a data source.
printf "This is the heartbeat_in: %s\n", $heartbeat_In;
my @rtn_In = $rrd->heartbeat($rrdfile, "bytesIn", 10);
my @rtn_Out = $rrd->heartbeat($rrdfile, "bytesOut", 10);
my @rtn_sec = $rrd->heartbeat($rrdfile, "faultsPerSec", 10); # This method will set a new heartbeat of a data source.
close(FH);
}
部分输出:
'myfilerrd' => {
'last_ds' => 'U',
'value' => undef,
'min' => '0',
'max' => undef,
'minimal_heartbeat' => 120,
'index' => 3,
'type' => 'DERIVE',
'unknown_sec' => 15
}
我不明白为什么该值未定义?