Memory Decreases dramtically when I minimize then resize my application? Memory leak? Microsoft Priority Setting?

[HughQuinn]

Help,

Problem 1: I have memory leak on my program In the process of debugging I noticed that my memory dramatically deecreases when I minimize my application which makes sense but when I mazimize again the memory is way lower than before???? Does anyone know why this would happen.

Startup= 150,000 K

Minimize = 30,000K

Maximize after minimized = 44,000K.

Problem 2: Every now and then the screen freezes and my graph skips a few points. Is there a way to make sure my program gets highest priority over anything else on the system. (Win XP). There is nothing else this computer is being used for. Noone is browsing net etc....

Specs: Pentium E5400 dual core 2.7 GHz, 3.2 GB of RAM, win XP pro 2002 SP3

Thanks in advance for your help.

Hugh

[altenbach]

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@HughQuinn wrote:

Startup= 150,000 K

Minimize = 30,000K

Maximize after minimized = 44,000K.

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See this post.

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@HughQuinn wrote:

Problem 2: Every now and then the screen freezes and my graph skips a few points. Is there a way to make sure my program gets highest priority over anything else on the system. (Win XP). There is nothing else this computer is being used for. Noone is browsing net etc....

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What does your program do? Can you show us some typical code?

Typical causes are:

1. Tight toplevel loops without a wait primitive, causing 100% CPU use.
2. Excessive code recalculations without actual need (calculations only need to occur if the inputs change, and not millions of times per second).
3. Misguided priority settings for the VI. For example if you set your VI to a very high priority, it will postpone front panel interactions and updated for the benefit of code execution and the VI seems unresponsive and sluggish. Leave the toplevel VI at normal priority.
4. ...

[Michael G]

Greetings HughQuinn,

In the case of performance questions, it may be very beneficial to know what version of LabVIEW you are running as performance can vary in unexpected ways between versions. 

Regards,

Michael G

[HughQuinn]

All,

thank you very much for your replies. i am using Labview 2010 with latest updates. I have seen this through a couple versions though. My applications is really quite large 30 Mb of source code. I am running several timed loops and I do have priorities set on them for a reason. But I do have a dedicated loop for updating my front panel do not use the timeout feature of the event structiure. The application is controlling a production tool of a factory floor and needless to say i can not afford any software crashes. The loops read in lots of hardware signals and output hardware signals. There is a loop that controls heaters using the PID loops. If you would send me your email I can ftp you the code if you would like a look. I will try and play around with the priorities. 

Regards,

Hugh

[altenbach]

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@HughQuinn wrote:

But I do have a dedicated loop for updating my front panel do not use the timeout feature of the event structiure.

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Does this loop have a reasonable wait inside?

How are you updating the controls from within that loop? For example if you do all this with value property nodes you might have a huge performance impact due to their synchronous nature.

[HughQuinn]

I actually do update some variables in the while loop with event structure now. I found a few controls that were not in a while loop This while loop has a wait of 100 ms and a timeout of 200 ms. I have a loop dedicated to updated all the rest of controls with a 500 ms wait. I update controls here by actually updating the controls themselves via global variables with a wait of 500 ms. I also have a graph that is updated on my front panel. 

[altenbach]

How much data is typically in the graph?

[HughQuinn]

I think i found my answer. Thank you all for your help

http://digital.ni.com/public.nsf/allkb/9EA3D4258E037B8A8625763300434D