VI calling from a multi-thread Teststand

Hello,
My test system tests four UUTs at the same time(with batch mode in TS), the code is based on LabVIEW and call from TS, so every step the same VI will be accessed by four thread. however, it runs quite slow even i set the reentrant execution in VI propertise.
My Quesition:
Can I do it like this in multi-thread mode of TS?
How can I make it fast? (convert VI to dll?????)
Any help will be appreciated.
Thanks,Steven

Hello Allen,
Thanks for your help.
Problem: I have a LabVIEW VI with parallel code blocks. These blocks run in parallel as expected when I run my VI directly or from a top level VI. However, the code blocks seem to run sequentially when I call my VI from TestStand. Why is this happening and how can I fix it?
Solution: In order to fix this behavior, simply set the VI Properties of "Execution" of your LabVIEW VI to "Other 1" or "Other 2". This change will make the parallel code blocks in your LabVIEW VI run in parallel as expected. To change this setting, from your LabVIEW VI, go to File»VI Properties. Select the Execution category. Change the Preferred Execution System to be either other 1 or other 2.
You need to make this change to any LabVIEW VI with parallel code blocks that is called from TestStand. The reason for this is that TestStand is using the LabVIEW ActiveX interface to run LabVIEW VIs. The LabVIEW ActiveX interface sets the caller's execution system to "User Interface" by default. This execution system is not recommended for a VI with parallel code blocks. If your LabVIEW VI's execution system is set to "Same as caller" (which is the default setting when creating a new LabVIEW VI), then it is executed in the User Interface thread when run through the LabVIEW ActiveX interface. This prevents the blocks to be executed in parallel.
In fact, only one block in my LabVIEW code, but it accessed by four thread from TS. I am sure that my VI can be accessed by four thread simultaneously if I enable the reentrant excution in VI property. I also have tried what mentioned in above document but no use.
However, if i only add a 1000ms delay to my LabView code instead of the 'calculation', it is fast enough! what is happening or something i set wrong?
I don't want to convert all my LabView code to DLL cos too many VIs here, and difficult for mantenance either.
Any other good solution???
Thank you Allen...
Steven

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What is multi threading?

Hi all,
What is multi threading? How to implement multi threading in ABAP?
Regards,
Bryan

Hi
How the vision connector framework works
The connector interacts with an SAP application using connector modules. The connector modules make calls to SAP's Native Interfaces and pass data (business object or event data) to and from an SAP application. The connector's flexible design enables different modules to be used for different tasks such as initializing the connector with the SAP application or passing business object data.
Communication between the connector and an SAP application
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Processing business objects
The connector is metadata driven. Metadata, in the WebSphere business integration system, is application-specific data that is stored in business objects and that assists a connector module in its interaction with the application. A metadata-driven connector module handles each business object that it supports based on metadata encoded in the business object definition rather than on instructions hard-coded in the connector module.
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The vision connector framework uses the value of the verb application-specific information in the top-level business object to call the appropriate connector module to process the business object. The verb application-specific information provides the classname of the connector module.
The verb application-specific information of most top-level business objects must identify the classname of the connector module. The syntax of this verb application-specific information is:
AppSpecificInfo = PartialPackageName.ClassName,
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AppSpecificInfo = sap.sapextensionmodule.VSapBOHandler,
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com.crossworlds.connectors.sap.sapextensionmodule.VSapBOHandler
Note:
The verb application-specific information of most top-level business objects must use a comma (,) delimiter after the connector classname. However, the Server verb, which is used by the RFC Server Module, is delimited instead by a semi-colon (;). For information about the Server verb, see How the RFC Server Module works and Supported verbs.
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Most business object processing is specific to each connector module. By default the connector uses the ABAP Extension Module. For more information on business object processing for the ABAP Extension Module, see Installing and customizing the ABAP Extension Module and Business object data routing to ABAP handlers. .
For more information on specifying verb application-specific information for the ALE Module, see Event processing and Processing multiple IDocs with a wrapper business object.
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Figure 4. Multi-Threading Architecture of the Connector for SAP
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The connector releases the connection handle after it receives the return code from SAP.
Setting the number of available connections
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SAP locks the dialog process while processing an interaction, releasing it only when the interaction completes. Therefore, multiple concurrent requests lock an equal number of dialog processes until processing finishes.
Important:
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Support for multiple connections
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<b>
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http://java.sun.com/developer/JDCTechTips/2003/tt1208.html#1
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HELP!....GUI crashes when i call a multi-threaded program from it

Hi..I have encountered a problem in my end of year project, which i cant see to solve. The problem is i am starting a multi-threaded program for a JButton on a GUI. All though this starts the other program it crashes the GUI completely how do i stop this.
this is the code i use to call the threaded program.
public void actionPerformed(ActionEvent e)
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thanks Mike

No there is no exceptions being given. this is one of the reasons why i dont no what to do. i thought myself that the threaded was taking all the resources and not going back to the GUI. if this is the case is there anyway that i can call back the GUI and keep the threaded program running?
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public shared Params as String
public shared Function SetValues(Param as String ) as String
Params = Param
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End Function
Which would be called in the detail section of the tablix, then in the header a textbox would hold the following expression:
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Thanks in advance!

Hi Angel,
Per my understanding that you want to dynamic display the group data in the report header, you have set page break based on the group, so when click to the next page, the report hearder will change according to the value in the group, when you are using
the shared variables you got the multiple thread safe problem, right?
I have tested on my local environment and can reproduce the issue, according to the multiple safe problem the better way is to use the harshtable behaves in the custom code, you have mentioned that you have tryied touse the harshtable but finally got
the same result as using the ReportItem!TextBox.Value, the problem can be cuased by the logic of the code that not works fine.
Please reference to the custom code below which works fine and can get all the expect value display on every page:
Shared ht As System.Collections.Hashtable = New System.Collections.Hashtable
Public Function SetGroupHeader( ByVal group As Object _
,ByRef groupName As String _
,ByRef userID As String) As String
Dim key As String = groupName & userID
If Not group Is Nothing Then
Dim g As String = CType(group, String)
If Not (ht.ContainsKey(key)) Then
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ht.Add(key, g)
Else
If Not (ht(key).Equals(g)) Then
ht(key) = g
End If
End If
End If
Return ht(key)
End Function
Using this exprssion in the textbox of the reportheader:
=Code.SetGroupHeader(ReportItems!Language.Value,"GroupName", User!UserID)
Links belowe about the hashtable and the mutiple threads safe problem for your reference:
http://stackoverflow.com/questions/2067537/ssrs-code-shared-variables-and-simultaneous-report-execution
http://sqlserverbiblog.wordpress.com/2011/10/10/using-custom-code-functions-in-reporting-services-reports/
If you still have any problem, please feel free to ask.
Regards
Vicky Liu

Cannot get bitmap from native DLL from multi threaded Java app.

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This all works fine within a single Java thread. If I do this multi threaded (thread 1 calls the native function and several seconds later, thread 2 calls the native function) I keep getting the last image of the first thread. Can enyone help me out?
I know that this is probably a question for MSDN but I just know that they will tell me its a JNI question.
The native code:
JNIEXPORT jobject JNICALL Java_somenamespace_getPicture
(JNIEnv *env, jclass cl, jstring serialNumber)
jobject jImage;
jclass jImageClass;
jmethodID jMethod;
jfieldID jField;
jintArray rgbArray;
char *str;
char *charArray;
int *intArray;
int w, h, index, type;
HBITMAP hbmp;
BITMAP bmp;
str = (char*)((*env)->GetStringUTFChars(env, serialNumber, NULL));
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jField = (*env)->GetStaticFieldID(env, jImageClass, "TYPE_INT_RGB", "I");
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index = 0;
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for (w = 0; w < bmp.bmWidth; ++w)
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int r = *(charArray + index * 3 + 2) & 0xFF;
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0, // int startX
0, // int startY
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bmp.bmHeight, // int height
rgbArray, // int[] rgbArray
0, // int offset
bmp.bmWidth); // int scansize
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free(charArray);
free(intArray);
return jImage;
}I already tried working with native HDCs (GetDC, CreateCompatibleBitmap, SelectObject, GetDIBits, ...) but this just complicates stuff and gives me the same result.

Have you verified what the "native DLL" gives you back on the second call?The HBITMAP handle returned is the same each call (no matter which thread). The actual BITMAP associated with this handle is only updated in the first thread.
How are you determining that the image is the same?If I point the camera (I don't get a stream, I just get individual images) to a moving scene, I get different images for each call from within the first thread. The second thread only gets the latest image from the first thread. There is no concurrency of the threads and all methods are synchronized.
Specifically did you verify that the problem is not that your test code itself is using the same instance?Yes, I tested the native side as well as the Java side. The BufferedImage is always an exact copy of the native BITMAP.
Try printing out the hash for each instance.I have written the image to a file in the native code itself to eliminate anything related to the mechanism of returning the BufferedImage. This had the same result.
The return values of all native calls all indicate successful calls.
I am suspecting the native side of creating a second graphical context for the second thread while it keeps refering to the first context.
(I will start a thread on the MSDN as well and will post here if anything turns up.)

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Hi,
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I will call my report from a multi record block, at the end of each record an icon is shown which the user can click to open the report.
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I created 2 hidden fields on the page P9_PARAMETER1, P9_PARAMETER2 with the same names as my bind variables and fill this in with the values #PARAMETER1#, #PARAMETER2# from the multi record block.
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hi khadeer,
create one report program and write the required code,and call this function module 'SSF_FUNCTION_MODULE_NAME' and give your smartform name and also when u activate ur smart form u will get one function module call that function module also and specify any tables used...
i think this solves ur problem...
any queries revert back..
pls reward points if helpful,
shylaja

Calling a delegate on the UI thread from a work thread inside a child class.

Hi All,
I've run into a snag developing a WPF multithreaded app where I need to call a method on the UI thread from my work thread, where the work thread is running a different class.
Currently I am trying to use a delegate and an event in the 2nd class to call a method in the 1st class on the UI thread. This so far is not working as because the 2nd class is running in its own thread, it causes a runtime error when attempting to call
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I've seen lots of solutions referring to using the dispatcher to solve this by invoking the code, however my work thread is running a different class than my UI thread, so it seems the dispatcher is not available?
Below is as simplified an example as I can make of what I am trying to achieve. Currently the below code results in a "The calling thread cannot access this object because a different thread owns it." exception at runtime.
The XAML side of this just produces a button connected to startThread2_Click() and a label which is then intended to be updated by the 2nd thread calling the updateLabelThreaded() function in the first thread when the button is clicked.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Threading;
using System.Threading;
namespace multithreadtest
public delegate void runInParent();
public partial class MainWindow : Window
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InitializeComponent();
threadUpdateLabel.Content = "Thread 1";
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thread2Class _Thread2 = new thread2Class();
_Thread2.runInParentEvent += new runInParent(updateLabelThreaded);
Thread thread = new Thread(new ThreadStart(_Thread2.threadedTestFunction));
thread.Start();
public void updateLabelThreaded()
threadUpdateLabel.Content = "Thread 2 called me!";
public class thread2Class
public event runInParent runInParentEvent;
public void threadedTestFunction()
if (runInParentEvent != null)
runInParentEvent();
I'm unfortunately not very experienced with c# so I may well be going the complete wrong way about what I'm trying to do. In the larger application I am writing, fundamentally I just need to be able to call a codeblock in the UI thread when I'm in a different
class on another thread (I am updating many different items on the UI thread when the work thread has performed certain steps, so ideally I want to keep as much UI code as possible out of the work thread. The work threads logic is also rather complicated as
I am working with both a webAPI and a MySQL server, so keeping it all in its own class would be ideal)
If a more thorough explanation of what I am trying to achieve would help please let me know.
Any help with either solving the above problem, or suggestions for alternative ways I could get the class in the UI thread to do something when prompted by the 2nd class in the 2nd thread would be appreciated.
Thanks :)

If I follow the explanation, I think you can use MVVM Light messenger.
You can install it using NuGet.
Search on mvvm light libraries only.
You right click solution in solution explorer and choose manage nugget...
So long as you're not accessing ui stuff on these other threads.
using GalaSoft.MvvmLight.Messaging;
namespace wpf_Tester
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
public MainWindow()
InitializeComponent();
Messenger.Default.Register<String>(this, (action) => ReceiveString(action));
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MessageBox.Show(msg);
Dispatcher.BeginInvoke((Action)delegate()
tb.Text = msg;
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Task.Factory.StartNew(() => {
Messenger.Default.Send<String>("Hello World");
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If you're then going to directly access properties of ui elements then you need to use Dispatcher.BeginInvoke to get back to the UI thread.
I do that with an anonymous action in that bit of code but you can call a method or whatever instead if your logic is more complicated or you need it to be re-usable.
http://social.technet.microsoft.com/wiki/contents/articles/26070.aspx
Hope that helps.
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Help calling JNI function from a java thread

I am using the following code to call a JNI fuction from a java thread:
public class CMSMessageHandler extends MessageHandler{
static{
System.loadLibrary("jastb");
public native int cmsReadIt(ByteBuffer buff);
private ByteBuffer dirbuf = null;
/** Creates a new instance of CMSMessageHandler */
public CMSMessageHandler() {
// allocate to max size datagram
dirbuf = ByteBuffer.allocateDirect(65536);
public void readMessages(){
/*Thread worker = new Thread(){
public void run(){*/
int count;
while (true){
try{
count = cmsReadIt(dirbuf);
} catch (Exception e){
e.printStackTrace();
worker.start();*/
public static void main(String[] args) {
CMSMessageHandler handler = new CMSMessageHandler();
handler.readMessages();
When I run this main method with the thread commented out, it works great. When I run the main method with the thread, it works great for a while, and then funny things start happening with the native library I am using. My native library uses shared memory, signals, and semaphores. It feels a bit like my java program is stomping on the resources that my native library is using, when a run the java program with a thread.
Is there something I don't know about calling native code from a thread? Should I be doing something explicitly to protect my native library's shared memory, signals, or semaphores?
Thanks,
Lisa.

Does the library do any initialization when loaded? Does it make a dangerous assumption that the thead calling cmdReadIt will always be the same thread that initially loaded it? Try loading the library in the worker thread instead of in the main thread via the static initializer.Yes. There is a call to another native method cmsOpenIt that does CMS initialization. I put cmsOpenIt as well as the System.loadLibrary("jastb") in the worker thread and I'm still experiencing the same problems.
Incidently, the mere presence of another Thread in this program does not seem to cause problems. It's only when I run calls to cmsReadIt in a thread that I get into trouble.
For example, this works fine:
public class CMSMessageHandler extends MessageHandler{
    public native int cmsReadIt(ByteBuffer buff);
    public ByteBuffer dirbuf = null;
    static {
        System.loadLibrary("jastb");
    public CMSMessageHandler() {
        // allocate to max size datagram
        dirbuf = ByteBuffer.allocateDirect(65536);
    public void readMessages(){
        try{
            int count = 0;
            while (true){
                count = cmsReadIt(dirbuf);
        } catch (Exception e){
    public static void main(String[] args) {
        CMSMessageHandler handler = new CMSMessageHandler();
        Thread worker = new Thread(){
            public void run(){
                while (true){
                    try{
                        Thread.currentThread().sleep(1000);
                        System.out.println("sleep thread.");
                    } catch (Exception e){
                        e.printStackTrace();
        worker.start();
        handler.readMessages();
    }Are there JVM flags that I should experiment with that might help mitigate/diagnose this problem?

Calling getAppletContext() from a working thread.

Hi guys,
I'm new to Java so all apologies if I'm asking a stupied question.
I have a simple applet that creates a working thread and I'm tring to call getAppletContext() from that thread.
Obviously my working thread has no instance of the Applet class so it fails.
I've try to create an instance of Applet, but I'm getting an error saying that the applet is not initialised.
This is my code:
class MyThread extends Thread
    String ThreadName;
    public MyThread(String threadName)
        ThreadName = threadName;
    @Override public void run()
        // ??? How to make the following line work ???
        getAppletContext().showDocument(new URL("javascript:alert(\"Calling from myThread\")"));
public class MyApplet extends Applet {
     public void init()
        // The following line works!
        getAppletContext().showDocument(new URL("javascript:alert(\"Calling from MyApplet)"));
        Thread WorkingThread = new MyThread("Thread1");
        WorkingThread.start();
}{code}
Please help,
Many thanks!
Salvador

Got it.
I needed to pass the keyword this to the thread constructor and then use that....
Many thanks!

VI calling from a multi-thread Teststand

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