Solver: out of memory

[MahavirSingh20]

While running a model with approximately 196 million non zero values in GridPath 0.9 (Python Version 3.9.13) on a system with 128 GB ram following error was received:
Using license file C:\Users\admin1\gurobi.lic
Read LP format model from file C:\Users\admin1\AppData\Local\Temp\tmpt_wpctwk.pyomo.lp
Reading time = 429.63 seconds
x47852276: 72619651 rows, 47852276 columns, 196612921 nonzeros
Changed value of parameter QCPDual to 1
Prev: 0 Min: 0 Max: 1 Default: 0
Changed value of parameter Threads to 4
Prev: 0 Min: 0 Max: 1024 Default: 0
Gurobi Optimizer version 9.0.3 build v9.0.3rc0 (win64)
Optimize a model with 72619651 rows, 47852276 columns and 196612921 nonzeros
Model fingerprint: 0x0456a20c
Coefficient statistics:
Matrix range [3e-08, 1e+02]
Objective range [1e+03, 8e+13]
Bounds range [0e+00, 0e+00]
RHS range [5e-07, 6e+06]
Warning: Model contains large objective coefficients
Consider reformulating model or setting NumericFocus parameter
to avoid numerical issues.

Concurrent LP optimizer: dual simplex and barrier
Showing barrier log only...

Traceback (most recent call last):
File "", line 5, in
File "C:\Users\admin1\AppData\Local\Programs\Python\Python39\lib\site-packages\pyomo\solvers\plugins\solvers\GUROBI_RUN.py", line 114, in gurobi_run
model.optimize()
File "model.pxi", line 843, in gurobipy.Model.optimize
gurobipy.GurobiError: Out of memory
ERROR: Solver (gurobi) returned non-zero return code (1)
ERROR: See the solver log above for diagnostic information.
ERROR:root:Solver (gurobi) did not exit normally

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[johnny-eee]

hi, i am also facing the memory insufficient issue, do u figure it out ? many thanks!

[PeterKlein11]

The log says that solver is running in concurrent mode, which means both simplex and barrier are trying to solve at the same time on a large model. Switching to barrier only should work.