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what is the maximum number of samples a shift register can hold

hi all,

I want to know what is the maximum number of samples a ‘shift register’ can hold in memeory pls reply me ASAP.

Regards,
Santhosh M
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Santhosh,

 

there is no limit you can reach by any means of common sense. If i had to guess, i'd say that a single loop can include up to 2^16 or 2^32 shift registers.

Regarding your question: How many can i use at a time without running into memory issues.....well that heavily depends on the data you keep in the shift registers. If you kepp only scalar numeric values like double (8 bytes), you can use as many shift registers as you like (with the given limit i stated above as guess). If you contain large images in your shift register, you probably can have only a single shift register....

 

hope this helps,

Norbert 

Norbert
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Hi Norbert,

In one while loop I am using singl Shift register. In given 2D array of DBL to shift register and I am appending every time some 16*1000 array to that 2D array after some time I am getting 'Not Enough Memory' error, so I want to know the limitation of shift register samples.   

Regards,
Santhosh M
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Santhosh,

 

your problem is not the shift register but the append array function. What is the maximum array size you want to handle? Keep in mind that your memory i

a) limited

b) fragmented

 

Both a and b are system dependend (e.g. do you have the /3GB option already set?), but they do limit your actual usable memory.

 

Norbert 

Norbert
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hi,

i want to know that array limit if i know that i will change in my application as per that

Regards,
Santhosh M
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Hi Santosh,

 

you can't say that for sure.

 

It would greatly help to init an array before the loop and use "replace subset" instead of "build array".

There is a KB article on managing large amounts of data, search for that!

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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The limit in the array size depends on your system. E.g. available RAM, fragmentation is important here (see also this thread). So nobody can answer your question except you. You have to benchmark your system.

Most important point: Preallocate the array, keep it in the shift register and work with "Replace Array Subset".

 

hope this helps,

Norbert 

Norbert
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thanks for reply i will try that and i will get back to you
Regards,
Santhosh M
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