Recovering Data from Frozen VI

[sezhesta]

Hello everyone,

I collect data in the form of arrays in my VI. I save the arrays to an Excel file in the end of the VI.

My VI became unresponsive for some reason after I collected the data and before I reach to the saving sequence, and all the LabVIEW related windows are dimmed in my Windows 7 ("not responding").

I am wondering if there is any way of recovering the data (the arrays) in such a situation. It has been hours and I did not force shut down the LabVIEW yet. It is still in not responding mode.

Thanks,

sezhesta

[altenbach]

Where do you keep "the data"? Local variables? shift regsiters? something else?

Could it be you were running out of memory? Obviously you learned a lesson that you should program it in a way to regularly stream the accumulated data to disk.

While it is most likely not possible to retrieve the data at this point, maybe we can find out why it locked up. How does it collect data? (external instrument, USB, etc.). What is the program architecture? Can you show us some code?

[crossrulz]

It is sounding like you are running out of memory.  If you are running that long, you really should think about logging the data on the fly.  I would recommend a Producer/Consumer architecture.

[sezhesta]

I was using global variables. Problem occured as I accidentally clicked refresh button for the VISA resource name address bar for a multimeter while the instrument was already connected. My code is a little bit complicated with many subVI so it would not be possible to troubleshoot without spending many hours.

Thank you for your comments.

[RavensFan]

Are you running in the development enviroment?

You might be able to create a subVI that calls that same global variable and writes a good value to it.  Then when you run that subVI, maybe the main VI (which is still running) starts using the good value again.

There are no guarantees that any past data will suddenly be recovered and saved.

[sezhesta]

Thank you RavensFan. The LabVIEW was completely unresponsive so it did not allow me to run any other VI in parallel.

I guess the conclusion is that the users should simply avoid leaving the data unsaved for long periods within the VI.