diff --git a/doc/user.xml b/doc/user.xml
index ac11af953..41b0299a8 100644
--- a/doc/user.xml
+++ b/doc/user.xml
@@ -1399,6 +1399,34 @@ database {
zgrep ^CONFIG_RT_GROUP_SCHED /proc/config.gz
+
+ You can verify whether the real-time scheduler is active with
+ the ps command:
+
+
+ # ps H -q `pidof -s mpd` -o 'pid,tid,cls,rtprio,comm'
+ PID TID CLS RTPRIO COMMAND
+16257 16257 TS - mpd
+16257 16258 TS - io
+16257 16259 FF 50 rtio
+16257 16260 TS - player
+16257 16261 TS - decoder
+16257 16262 FF 50 output:ALSA
+16257 16263 IDL 0 update
+
+
+ The CLS column shows the CPU scheduler;
+ TS is the normal scheduler;
+ FF and RR are
+ real-time schedulers. In this example, two threads use the
+ real-time scheduler: the output thread and
+ the rtio (real-time I/O) thread; these two
+ are the important ones. The database update thread uses the
+ idle scheduler ("IDL in
+ ps), which only gets CPU when no other
+ process needs it.
+
+
There is a rumor that real-time scheduling improves audio