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TDMS File Size Unexpected

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I'm trying to keep track of the TDMS File size as I write it and my options are as follows:

 

1) Log (Double - Seconds Count) & (Double - Data)

2) Log (Double - Data)

 

When I log just the data, I just take the 8 Bytes that make up the double and add them to the total count which I keep in a U64 shift register. I am able to accurately cut off the TDMS file and start a new one at a pre-determined size. 

 

When I log the data + timestamp (seconds double), I am almost high by a factor of 10. 

 

I assumed the math was the following:

 

(Data Size) X (# of Channels) X (# of Rows of Data) + (Metadata) = File Size

 

So if that is true then why attached file so off in size? Windows says its 9M, but when I add up the data it should be around .9M.

 

(Data Size = 😎 X (2 Channels) X (62436 Rows)  = 0.998976M

 

Let me know where my logic is flawed.

 

Thanks!  

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Solution
Accepted by rkmadse

Try defragmenting the TDMS file after you're done writing.

Lucian
CLA
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