From ca88b0a32cb4fab977b5164cb811ef2b272934bd Mon Sep 17 00:00:00 2001
From: Florian Forster <octo@collectd.org>
Date: Sat, 13 Sep 2014 10:25:31 +0200
Subject: [PATCH] collectd.conf(5): Document the ReportDegraded" option.

---
 src/collectd.conf.in  |  1 +
 src/collectd.conf.pod | 27 ++++++++++++++++++++++-----
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index d7a5990c..38b2ba46 100644
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -282,6 +282,7 @@
 
 #<Plugin "battery">
 #  ValuesPercentage false
+#  ReportDegraded
 #</Plugin>
 
 #<Plugin "bind">
diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 0a7ed9b6..ba99b60d 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -988,14 +988,31 @@ laptop batteries.
 
 =over 4
 
-=item ValuesPercentage B<false>|B<true>
+=item B<ValuesPercentage> B<false>|B<true>
 
-When enabled, charged capacity is reported as a percentage, e.g. "42% capacity
-remaining". Otherwise the capacity is stored as reported by the battery, most
-likely in "Wh". This option does not work with all input methods, in particular
-when only C</proc/pmu> is available on an old Linux system.
+When enabled, remaining capacity is reported as a percentage, e.g. "42%
+capacity remaining". Otherwise the capacity is stored as reported by the
+battery, most likely in "Wh". This option does not work with all input methods,
+in particular when only C</proc/pmu> is available on an old Linux system.
 Defaults to B<false>.
 
+=item B<ReportDegraded> B<false>|B<true>
+
+Typical laptop batteries degrade over time, meaning the capacity decreases with
+recharge cycles. The maximum charge of the previous charge cycle is tracked as
+"last full capacity" and used to determine that a battery is "fully charged".
+
+When this option is set to B<false>, the default, the I<battery plugin> will
+only report the remaining capacity. If the B<ValuesPercentage> option is
+enabled, the relative remaining capacity is calculated as the ratio of the
+"remaining capacity" and the "last full capacity". This is what most tools,
+such as the status bar of desktop environments, also do.
+
+When set to B<true>, the battery plugin will report three values: B<charged>
+(remaining capacity), B<discharged> (difference between "last full capacity"
+and "remaining capacity") and B<degraded> (difference between "design capacity"
+and "last full capacity").
+
 =back
 
 =head2 Plugin C<bind>
-- 
2.30.2