GAMS limit errors

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GAMS generates errors when it runs out of time, authorized iterations or space either during the GAMS execution of the problem or inside the solver.  In turn, the LOG file can contain messages such as

 

--- Starting compilation

--- AGRESTE.GMS(312) 1 Mb

--- Starting execution

--- AGRESTE.GMS(307) 1 Mb

--- Generating model agreste

--- AGRESTE.GMS(309) 1 Mb

---    52 rows, 101 columns, and 665 non-zeroes.

--- Executing BDMLP

 

 BDMLP 1.3     Mar 21, 2001 WIN.BD.NA 20.0 056.043.039.WAT

 

 Reading data...

 Work space allocated           --    0.06 Mb

 

    Iter    Sinf/Objective  Status    Num  Freq

       1    5.95393922E+02  infeas      6     1

      20    2.12198277E-02  infeas      1

 SOLVER STATUS: 3 RESOURCE INTERRUPT

 MODEL STATUS : 6 INTERMEDIATE INFEASIBLE

 

**** SOLVER STATUS     3 RESOURCE INTERRUPT

**** MODEL STATUS      6 INTERMEDIATE INFEASIBLE

**** OBJECTIVE VALUE                0.0000

 

•Resources interrupt which indicates GAMS runs out of authorized time which is fixed by expanding the resource limit –

 

 OPTION RESLIM = 50000;

 

 where the 50000 may be replaced with any number. Etlim can also be used.

•Too many iterations which is fixed by expanding the iteration limit –

 

 OPTION ITERLIM = 100000;

 

 where the 100000 may be replaced with any number. As of 23.1 the default iteration limit (IterLim) was been increased from 10000 to 2e9. Setting IterLim to INF will not work since it is treated as an integer by GAMS and many solvers. Some solver, e.g. GAMS/Gurobi, recognize 2e9 and set the solver iteration limit to infinity

•Not enough work space which is fixed by expanding the workspace limit –

 

 OPTION work = 30;

 

 where the number (30) gives the Work space limit in megabytes and should not exceed the computer RAM.