[Mixxx-devel] Major Linux performance fix

[Andreas Pflug]

Using the outline skin on Debian 5.0, I see mixxx consuming 13 % CPU, 
and xorg 32% even when there's no visual change.

Digging a little on the performance issues mentioned in the wiki, I 
found that preventing ControlObject from changing unchanged values does 
the trick, see attached trivial patch against trunk. It reduces xorg CPU 
usage to a minimum when there's no display update.

As soon as I play, the cpu usage rises again (mostly in xorg, caused by 
wVuMeter updates), which I reduced drastically by using repaint() 
instead of update() in WWidget::setValue().

Regards,

Andreas



Index: widget/wwidget.cpp
===================================================================
--- widget/wwidget.cpp	(revision 2748)
+++ widget/wwidget.cpp	(working copy)
@@ -132,7 +132,7 @@
 void WWidget::setValue(double fValue)
 {
     m_fValue = fValue;
-    update();
+    repaint();
 }
 
 void WWidget::setOnOff(double d)
Index: controlpotmeter.cpp
===================================================================
--- controlpotmeter.cpp	(revision 2748)
+++ controlpotmeter.cpp	(working copy)
@@ -87,6 +87,8 @@
 
 void ControlPotmeter::setValueFromThread(double dValue)
 {
+    if (dValue == m_dValue) return;
+
     if (dValue>m_dMaxValue)
         m_dValue = m_dMaxValue;
     else if (dValue<m_dMinValue)
Index: controlobject.cpp
===================================================================
--- controlobject.cpp	(revision 2748)
+++ controlobject.cpp	(working copy)
@@ -165,12 +165,16 @@
 
 void ControlObject::setValueFromThread(double dValue)
 {
+    if (m_dValue == dValue) return;
+
     m_dValue = dValue;
     emit(valueChanged(m_dValue));
 }
 
 void ControlObject::set(double dValue)
 {
+    if (m_dValue == dValue) return;
+
     setValueFromEngine(dValue);
     m_sqQueueMutexChanges.lock();
     m_sqQueueChanges.enqueue(this);
@@ -179,6 +183,8 @@
 
 void ControlObject::add(double dValue)
 {
+    if (!dValue) return;
+
     setValueFromEngine(m_dValue+dValue);
     m_sqQueueMutexChanges.lock();
     m_sqQueueChanges.enqueue(this);
@@ -187,6 +193,8 @@
 
 void ControlObject::sub(double dValue)
 {
+    if (!dValue) return;
+
     setValueFromEngine(m_dValue-dValue);
     m_sqQueueMutexChanges.lock();
     m_sqQueueChanges.enqueue(this);
------------------------------------------------------------------------------
Crystal Reports &#45; New Free Runtime and 30 Day Trial
Check out the new simplified licensign option that enables unlimited
royalty&#45;free distribution of the report engine for externally facing 
server and web deployment.
http://p.sf.net/sfu/businessobjects_______________________________________________
Mixxx-devel mailing list
Mixxx-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/mixxx-devel