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<div><span style="font-family: "Times New Roman", Times, serif;">Dear Petsc developers and Users,</span></div>
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<div><font size="3"><span style="font-size: 12pt; font-family: "Times New Roman", Times, serif;">I am constructing a very large matrices (~5,000,000*5,000,000) for a generalized eigenvalue problem in MPIAIJ format across multiple nodes. The program is to be
run on a shared HPC cluster using Slurm workload manager. Due to multiple loops and calculations needed, the matrix construction time is long (may span for more than a week). </span></font></div>
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<div><font size="3"><span style="font-size: 12pt; font-family: "Times New Roman", Times, serif;">Hence, I am trying to see if I can implement checkpoints into the codes, so that the matrix can be constructed partially through multiple job submissions, each
job picking up from where the previous one left until the matrix is fully built and we can write the global matrix into a binary file for further eigenvalue analysis. My questions are: </span></font></div>
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<div><font size="3"><span style="font-size: 12pt; font-family: "Times New Roman", Times, serif;">Does Petsc MPIAIJ format is amenable to such check points? </span></font></div>
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<div><font size="3"><span style="font-size: 12pt; font-family: "Times New Roman", Times, serif;">If so, are there any subroutines/functions that I can start with? </span></font><br>
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<div><span style="font-family: "Times New Roman", Times, serif;">I appreciate any comments/suggestions. </span></div>
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<div><span style="font-family: "Times New Roman", Times, serif;">Thank you, <br>
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<div><span style="font-family: "Times New Roman", Times, serif;">D. N. Pham</span><br>
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