=item
+Apache server stats (I<apache>)
+
+=item
+
+Apple hardware sensors (I<apple_sensors>, Darwin only)
+
+=item
+
Battery status (I<battery>)
=item
Number of users logged into the system (I<users>)
+=item
+
+System ressources used by VServers (I<vserver>)
+
+=item
+
+Wireless network stats (I<wireless>)
+
=back
=head1 OPTIONS
=head1 SPECIAL PLUGINS
+=head2 apache
+
+This module connects to an Apache webserver and expects the output produced by
+B<mod_status.c>. If requires B<libcurl> to set up the HTTP connection and issue
+the request(s). The following is a sample config for the Apache webserver. The
+use of C<ExtendedStatus on> is mandatory.
+
+ ExtendedStatus on
+ <IfModule mod_status.c>
+ <Location /mod_status>
+ SetHandler server-status
+ </Location>
+ </IfModule>
+
+This plugin requires further configuration. Please read L<collectd.conf(5)>.
+
=head2 cpufreq
This module reads F</sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq> (for
the first CPU installed) to get the current CPU frequency. If this file does
not exist make sure B<cpufreqd> (L<http://cpufreqd.sourceforge.net/>) or a
-similar tool is installed.
+similar tool is installed and an "cpu governor" (that's kernel module) is
+loaded.
=head2 mysql
The B<hddtemp> homepage can be found at
L<http://www.guzu.net/linux/hddtemp.php>.
-=head1 RRD FILES
+=head2 vserver
-The RRD files are created automatically with the following RRAs:
+B<VServer> support is only available for Linux. It cannot yet be found in a
+vanilla kernel, though. To make use of this plugin you need a kernel that has
+B<VServer> support built in, i.e. you need to apply the patches and compile
+your own kernel, which will then provide the /proc/virtual filesystem that is
+required by this plugin.
- RRA:AVERAGE:0.2:6:1500
- RRA:AVERAGE:0.1:180:1680
- RRA:AVERAGE:0.1:2160:1520
- RRA:MIN:0.2:6:1500
- RRA:MIN:0.1:180:1680
- RRA:MIN:0.1:2160:1520
- RRA:MAX:0.2:6:1500
- RRA:MAX:0.1:180:1680
- RRA:MAX:0.1:2160:1520
+The B<VServer> homepage can be found at L<http://linux-vserver.org/>.
-Since collectd uses a 10 second I<step> the RRAs contain the following
-timespans:
+=head1 RRD FILES
- Resolution | Data points | Timespan
- -----------+-------------+----------
- 60 seconds | 1500 | 25 hours
- 30 minutes | 1680 | 35 days
- 6 hours | 1520 | 380 days
+The RRD files are created automatically. The size of the RRAs depend on the
+compile time settings of I<step> and I<width>. With the default values (I<step>
+= B<10>, I<width> = B<1200>) the following RRAs are created:
+
+ RRA:AVERAGE:0.1:1:8640
+ RRA:AVERAGE:0.1:50:1210
+ RRA:AVERAGE:0.1:223:1202
+ RRA:AVERAGE:0.1:2635:1201
+ RRA:MIN:0.1:1:8640
+ RRA:MIN:0.1:50:1210
+ RRA:MIN:0.1:223:1202
+ RRA:MIN:0.1:2635:1201
+ RRA:MAX:0.1:1:8640
+ RRA:MAX:0.1:50:1210
+ RRA:MAX:0.1:223:1202
+ RRA:MAX:0.1:2635:1201
+
+By default collectd uses a 10 second I<step>. Thus the RRAs contain the
+following timespans. If you've changed the I<step> at compile time you will
+have calculate resolution and timespan yourself.
+
+ PDP per CDP | Resolution | Data points | Timespan
+ ------------+--------------+-------------+---------
+ 1 | 10.0 seconds ! 8640 ! 1 day
+ 50 | 8.3 minutes | 1210 | 1 week
+ 223 | 37.2 minutes | 1202 | 1 month
+ 2635 | 7.3 hours | 1201 | 1 year
The DS'es depend on the module creating the RRD files:
DS:users:GAUGE:25:0:65535
+=item VServer load (F<vserver-I<E<lt>xidE<gt>>/load.rrd>)
+
+ DS:shortterm:GAUGE:25:0:100
+ DS:midterm:GAUGE:25:0:100
+ DS:longterm:GAUGE:25:0:100
+
+=item VServer threads (F<vserver-I<E<lt>xidE<gt>>/threads.rrd>)
+
+ DS:total:GAUGE:25:0:65535
+ DS:running:GAUGE:25:0:65535
+ DS:uninterruptible:GAUGE:25:0:65535
+ DS:onhold:GAUGE:25:0:65535
+
+=item VServer network traffic (F<vserver-I<E<lt>xidE<gt>>/traffic-I<E<lt>nameE<gt>>.rrd>)
+
+ DS:incoming:COUNTER:25:0:9223372036854775807
+ DS:outgoing:COUNTER:25:0:9223372036854775807
+ DS:failed:COUNTER:25:0:9223372036854775807
+
+=item VServer processes (F<vserver-I<E<lt>xidE<gt>>/vs_processes.rrd>)
+
+ DS:total:GAUGE:25:0:65535
+
+=item VServer memory usage (F<vserver-I<E<lt>xidE<gt>>/vs_memory.rrd>)
+
+ DS:vm:GAUGE:25:0:9223372036854775807
+ DS:vml:GAUGE:25:0:9223372036854775807
+ DS:rss:GAUGE:25:0:9223372036854775807
+ DS:anon:GAUGE:25:0:9223372036854775807
+
=back
=head1 SEE ALSO