Hello PETSc developpers, 

I have been using SLEPc and PETSc for solving my sparse systems for a
small time now, and have been very satisfied with everything. 

However, I have been running into an error lately, and I have been
unable to find any online resource  that talks about this specific
error. 

I use SLEPc to find all the eigenvalues of certain tridiagonal and
symmetric matrices. I set the solver to find all the eigenvalues in a
large interval ([0;10] for example) using the spectrum splicing
technique. I use MUMPS because I would like to perform this calculation
in parallel later on, but for now I am doing it sequentially. 

While the solver works very well for small enough matrices (n=2000),
when I increase the matrix size to around 10000, I get this error that I
do not really understand:

[0]PETSC ERROR: First shift renders no information 

Could someone please enlighten me as to what this error means? I don't
know if it's relevant but I am using older version of PETSc (3.8.4) and
SLEPc (3.8.2). 

I apologize in advance if this question has been answered somewhere
already. 

Thank you very much, 

Sincerely,

Desforges Perceval

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