Recording 1 hour of waveform chart with 64 inputs?

I am using 64 inputs at 100Hz each and I'd like to visualise each of these inputs for at least 1hour.
I use 8 charts of 8 inputs each. I made several tests :
I put a big history lenght on the waveform chart--> the ram disk (512Mo) is not abble to store all the information.
When the chart history length is more than 10000 long, it doesn't work well.
When we put a small chart history lenght 1024, waves are deleted when we resize the window. The waveformchart can only record 1min of datas.
Is there a way to visualise one hour or more of acquisition at 100Hz with 64 inputs?
Thank you very much for your help
Ludovic Charpentier
PS : I use a P4

Hi,
Each time you acquire a new point, you put it in a waveform chart. That means that, each time, you make an array bigger and LV will give it a new memory allocation ... This will give a very slow process if you manipulate millions of points (this the case 3600*100*64 = around 23 040 000 of points).
What I can suggest you is to save all datas in a file and you plot only a part of the acquisition (5000 points for example). This will allow you to see a part of the acquisition graph in "real time" and if you want to have all acquired points in only one graph, you will be able to do that at the end of the acquisition.
Remember that memory allocation is easy in Labview because you do not have to care about anything. But behind, in the hidden part, big arrays are allocated at each loop iteration and this effectively slowes down your process.
Hope it will help you,
Regards
David D. - Application Engineer - NI France

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