I have a relatively large system (~25000 lines so far) for monitoring radio-related devices. It shows graphs and such using latest version of ZedGraph.
The program is coded using C# on VS2010 with Win7.
The problem is:
- when I run the program from within VS, it runs slow
- when I run the program from the built EXE, it runs slow
- when I run the program though Performance Wizard / CPU Profiler, it runs Blazing Fast.
- when I run the program from the built EXE, and then start VS and Attach a profiler to ANY OTHER PROCESS, my program speeds up!
I want the program to always run that fast!
Every project in the solution is set to RELEASE, Debug unmanaged code is DISABLED, Define DEBUG and TRACE constants is DISABLED, Optimize Code - I tried either, Warning Level - I tried either, Suppress JIT - I tried either,
in short I tried all the solutions already proposed on StackOverflow - none worked. Program is slow outside profiler, fast in profiler.
I don't think the problem is in my code, because it becomes fast if I attach the profiler to other, unrelated process as well!
Please help!
I really need it to be that fast everywhere, because it's a business critical application and performance issues are not tolerated...
UPDATES 1 - 8 follow
--------------------Update1:--------------------
The problem seems to Not be ZedGraph related, because it still manifests after I replaced ZedGraph with my own basic drawing.
--------------------Update2:--------------------
Running the program in a Virtual machine, the program still runs slow, and running profiler from the Host machine doesn't make it fast.
--------------------Update3:--------------------
Starting screen capture to video also speeds the program up!
--------------------Update4:--------------------
If I open the Intel graphics driver settings window (this thing: http://www.intel.com/support/graphics/sb/img/resolution_new.jpg)
and just constantly hover with the cursor over buttons, so they glow, etc, my program speeds up!.
It doesn't speed up if I run GPUz or Kombustor though, so no downclocking on the GPU - it stays steady 850Mhz.
--------------------Update5:--------------------
Tests on different machines:
-On my Core i5-2400S with Intel HD2000, UI runs slow and CPU usage is ~15%.
-On a colleague's Core 2 Duo with Intel G41 Express, UI runs fast, but CPU usage is ~90% (which isn't normal either)
-On Core i5-2400S with dedicated Radeon X1650, UI runs blazing fast, CPU usage is ~50%.
--------------------Update6:--------------------
A snip of code showing how I update a single graph (graphFFT is an encapsulation of ZedGraphControl for ease of use):
public void LoopDataRefresh() //executes in a new thread
{
while (true)
{
while (!d.Connected)
Thread.Sleep(1000);
if (IsDisposed)
return;
//... other graphs update here
if (signalNewFFT && PanelFFT.Visible)
{
signalNewFFT = false;
#region FFT
bool newRange = false;
if (graphFFT.MaxY != d.fftRangeYMax)
{
graphFFT.MaxY = d.fftRangeYMax;
newRange = true;
}
if (graphFFT.MinY != d.fftRangeYMin)
{
graphFFT.MinY = d.fftRangeYMin;
newRange = true;
}
List<PointF> points = new List<PointF>(2048);
int tempLength = 0;
short[] tempData = new short[2048];
int i = 0;
lock (d.fftDataLock)
{
tempLength = d.fftLength;
tempData = (short[])d.fftData.Clone();
}
foreach (short s in tempData)
points.Add(new PointF(i++, s));
graphFFT.SetLine("FFT", points);
if (newRange)
graphFFT.RefreshGraphComplete();
else if (PanelFFT.Visible)
graphFFT.RefreshGraph();
#endregion
}
//... other graphs update here
Thread.Sleep(5);
}
}
SetLine is:
public void SetLine(String lineTitle, List<PointF> values)
{
IPointListEdit ip = zgcGraph.GraphPane.CurveList[lineTitle].Points as IPointListEdit;
int tmp = Math.Min(ip.Count, values.Count);
int i = 0;
while(i < tmp)
{
if (values[i].X > peakX)
peakX = values[i].X;
if (values[i].Y > peakY)
peakY = values[i].Y;
ip[i].X = values[i].X;
ip[i].Y = values[i].Y;
i++;
}
while(ip.Count < values.Count)
{
if (values[i].X > peakX)
peakX = values[i].X;
if (values[i].Y > peakY)
peakY = values[i].Y;
ip.Add(values[i].X, values[i].Y);
i++;
}
while(values.Count > ip.Count)
{
ip.RemoveAt(ip.Count - 1);
}
}
RefreshGraph is:
public void RefreshGraph()
{
if (!explicidX && autoScrollFlag)
{
zgcGraph.GraphPane.XAxis.Scale.Max = Math.Max(peakX + grace.X, rangeX);
zgcGraph.GraphPane.XAxis.Scale.Min = zgcGraph.GraphPane.XAxis.Scale.Max - rangeX;
}
if (!explicidY)
{
zgcGraph.GraphPane.YAxis.Scale.Max = Math.Max(peakY + grace.Y, maxY);
zgcGraph.GraphPane.YAxis.Scale.Min = minY;
}
zgcGraph.Refresh();
}
.
--------------------Update7:--------------------
Just ran it through the ANTS profiler. It tells me that the ZedGraph refresh counts when the program is fast are precisely two times higher compared to when it's slow.
Here are the screenshots:
I find it VERY strange that, considering the small difference in the length of the sections, performance differs twice with mathematical precision.
Also, I updated the GPU driver, that didn't help.
--------------------Update8:--------------------
Unfortunately, for a few days now, I'm unable to reproduce the issue... I'm getting constant acceptable speed (which still appear a bit slower than what I had in the profiler two weeks ago) which isn't affected by any of the factors that used to affect it two weeks ago - profiler, video capturing or GPU driver window. I still have no explanation of what was causing it...
See Question&Answers more detail:
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