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LinkObject Error

Open GibbsJR opened this issue 2 years ago • 1 comments

Hi Tyson,

I have had another error I was hoping you could help identify the cause.

In my notebook I set off an iterative algorithm, which starts without complaining, then after several iterations I get this 'LinkObject' error, which breaks everything and I have to reset the notebook. I'm really not sure what causes it. I was wondering if my memory was blowing up for some reason, so I was using the 'MemoryInUse[]' function to print out the memory after each iteration, which as you can see does not seem to be significantly increasing. For reference I am operating on a ~10 qubit system with the density matrix simulator on a Tesla V100, which I think it should be able to handle comfortably.

Please let me know if you have suggestions of what may be the cause, your help is much appreciated.

Thanks, Joe

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GibbsJR avatar Jul 19 '23 21:07 GibbsJR

Hi Joe,

Sincere apologies for the enormous delay! Somehow I missed this issue - we can always discuss these in-person now ;) The error you encountered seems a severe one; Mathematica disconnected from the QuESTlink backend process, possibly because that process crashed or communicated invalidly to the Mathematica kernel, or something timed out.

This is most likely a bug (and a worrisome one!) in QuESTlink's C++ backend. I share your suspicions that a memory leak caused an overflow somewhere; maybe local stack memory (much smaller than your total ~.2GB) was somewhere exceeded. Could you give me some more information about the code you were running during this crash? (if you even remember! I imagine I'm hopelessly, uselessly late eheh)

TysonRayJones avatar Dec 18 '23 13:12 TysonRayJones