User Tools

Site Tools


solver:error_1001_out_of_memory

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
solver:error_1001_out_of_memory [2017/09/02 19:35]
support
— (current)
Line 1: Line 1:
-====== Error 1001: Out of Memory ====== 
-This message indicates that Cplex is running out of memory while solving the model. \\ 
-The [[http://​support.gams.com/​doku.php?​id=check_list|log file]] will provide more information about the size of the model and where in the solution process the memory message appears: 
-  * during preprocessing of the model and while solving the preprocessed model 
-  * during the branch & bound process 
-  * during the final solve and the calculation of the marginals.  ​ 
-The simplest solution is to decrease the size of the model or add more (physical) memory. ​ 
- ​Please note that the 32 bit version of the windows operating limits any GAMS or solver process to ~1.7 Gb, hence, consider to use the 64 bit version. Please [[installation:​do_i_have_a_32bit_or_a_64_bit_version_of_windows|look here]] for more information. ​ 
  
-One can try to save some memory by: 
-  - Make sure that only the necessary equations get generated (check chapter 11.6 of the GAMS User's Guide or the Mc Carl Expanded GAMS User Guide for more information) 
-  - Use the GAMS option ''​model_name.holdfixed 1'',​ if there are many fixed variables 
-  - Use the GAMS option ''​solvelink 0''​ (and not 1,  2, 3, 4 or 5) 
-  - Save memory by not passing on names to the solver: ''​model_name.dictfile=0''​ 
-  - Use a Cplex option file (see the [[https://​www.gams.com/​latest/​docs/​S_CPLEX.html|Cplex Manual]], in particular [[https://​www.gams.com/​latest/​docs/​S_CPLEX.html#​CPLEX_PHYSICAL_MEMORY_LIMITATIONS|Physical Memory Limitations]] and [[https://​www.gams.com/​latest/​docs/​S_CPLEX.html#​CPLEX_RUNNING_OUT_OF_MEMORY_FOR_MIP_PROBLEMS|Running Out of Memory for MIP Problems]] for details): ​ 
-    * Do not load GAMS names (''​names no''​) ​ 
-    * Do not use multiple threads (''​threads 1''​) ​ 
-    * Conserve memory where possible (''​memoryemphasis 1''​) 
-    * Use  the Simplex algorithm ​ (''​lpmethod 1 or 2''​) instead of the Barrier algorithm (''​lpmethod 4''​) 
-    * Increase the refactorization frequency (decrease ''​reinv''​) 
-    * (MIP) Let Cplex store information on disk (''​nodefileind 2 or 3''​ / ''​workmem''​) 
-    * (MIP) Do not solve the final LP (''​solvefinal 0''​). Please keep in mind that without solving the final LP, the solution will be primal only - no marginals will be reported. ​ 
-    * (MIP) Set option ''​nodesel''​ to use a best estimate strategy (''​nodesel 2''​) or more drastically a depth-first-search (''​nodesel 0''​). 
-    * (MIP) Set option ''​varsel''​ to use strong branching (''​varsel 3''​). 
-    * (MIP) Turn off cut generation (''​cuts -1''​). ​ 
-    * (Barrier) Do not do a crossover at the end of the barrier optimization (''​barcrossalg -1''​). In that case the solution will also be primal only - no marginals will be reported. ​ 
-Of course, conserving memory may impact performance in some models. 
IMPRESSUM / LEGAL NOTICEPRIVACY POLICY solver/error_1001_out_of_memory.1504373720.txt.gz ยท Last modified: 2017/09/02 19:35 by support