Labview 8.2 very very very slow

[Garraty]

Hi to all.

I posted the same question in NI forum, but, the problem is serous for me, so I try also in this community.

I upgraded a large SW developed in LV 7.1 to LV 8.2. After some error corrections I saw that a large Vi in LV 7.1 (a Vi template, .vit) that was 18 MB, in LV8.2 was 2.6 MB !

The editing of this Vi is very very very slow, and it's unacceptable. When I save it I can have a coffee break !!

Also, to open the reference to this Vi it's necessary 35-40s but in LV 7.1 2 seconds were enough.

In the Vi there isn't BMP, large strings.., it's saved in 8.2 format (I coverted and then I saved it), there is a digital waveform graph initially empty and there is 2 slide bars that overlap the graph (I update their position when windows resize).

I discovered where LV "wait " a lot of time. The Vi is a "clone Vi ", so I open it in the way that you can view in the attached vi. In the Open Vi Refernce block (there is a break point) the CPU work at 100% for a lot of time and , I think, this is the only reason of slowness . After this block, the execution is ok and it's output is:

VI name: READ_DIGITAL 12.vi

VI path:

Application instance: Main Application Instance

Refnum (in hex): 0xCEB00025

When I open the vi to edit it, itsn't slow..but it's very slow the editing...

Any suggestion to solve this big problem ?

Thanks and regards

Download File:post-6435-1160390940.vi

[Dan Hedges]

First of all, it is not unusual for a VI to be much smaller in version 8.0 or 8.2 than it was in 7.1. In version 8.0, we implemented a new format for saved VIs that included a new form of compression, and that caused the size of typical VIs to decrease 55%. (VIs saved in LLBs decreased approximately 20%.) Obviously, you're seeing a bigger savings than the typical case. Without seeing the huge VI, I won't be able to tell you why it's so much smaller.

As for the performance problems you see, I can't say what's happening without looking at the VI. I have not heard of this problem before. It sounds like one of the algorithms we run over your VI on most editing operations got more complex, but I don't know which one. Is there any way you could make the big VI available?

[LAVA 1.0 Content]

Hi to all.

I posted the same question in NI forum, but, the problem is serous for me, so I try also in this community.

I upgraded a large SW developed in LV 7.1 to LV 8.2. After some error corrections I saw that a large Vi in LV 7.1 (a Vi template, .vit) that was 18 MB, in LV8.2 was 2.6 MB !

The editing of this Vi is very very very slow, and it's unacceptable. When I save it I can have a coffee break !!

I beleave the coffee breaks are due to recompiling the code. I've seen this slow editing behaviour in a class private data control that is referenced by hundreds of VIs. When ever I change the control, LabVIEW recompiles all the VIs referencing to this control. It does it even when I just move something a little in the control. It's pretty annoying, I must agree.

However why the recompiling happens and how it can be avoided cannot be said with the information you have provided so far. You either must provide us the VI or contact your local National Instruments support (if you have a support contract or if you can identify a defenite bug in LabVIEW). Verify that your VIs are not referring to any VIs in LabVIEW 7.1.1 world.

Then try this trick also. Make sure all your VIs in the project are simultaneously open. You can verify this by dropping all the VIs as a subVI into a program block diagram. Then press ctrl +shift + click on the run-button. This forces recompiling all the code. Save everything in the end. And yes, change the .vit to .vi as you don't need .vit in LabVIEW to open multiple refecences to same file. Also make sure that you use 0x08 prepare for reentrant call in the open VI reference is you are about the call multiple instances of the same VI.