[Help-glpk] memory problem solving a 4221 var and 1336 constraints

[Hernandez Florent]

memory problem solving a 4221 var and 1336 constraintsI have a memory problem 
solving a simplex (real variables) with  4221 var and 1336 inequality 
constraints
The file written by glpk routine glp_write_lp() amounts to 140 MBytes.
When I read this file and try to solve it, memory usage climbs up to 1.5 Gbytes.
Then the malloc death sentence falls "umalloc: size = 8016; malloc failed ".

Why does my problem need so much RAM within glpk ?
I would expect far less.

When glpk reads the file, it says it has 1336 rows (correct), 8 910 531 columns 
(why?)
and 1 312 263 non zero values in the matrix.

Any help ?
Is it possible to handle glpk so that it minimises memory usage ?
Or should I think about another solver (which I don't want to!)

thanks,


Florent HERNANDEZ

I have a memory problem solving a simplex (real variables) with  4221 var and 1336 inequality constraints
The file written by glpk routine glp_write_lp() amounts to 140 MBytes.
When I read this file and try to solve it, memory usage climbs up to 1.5 Gbytes.
Then the malloc death sentence falls "umalloc: size = 8016; malloc failed ".

Why does my problem need so much RAM within glpk ?
I would expect far less.

When glpk reads the file, it says it has 1336 rows (correct), 8 910 531 columns (why?)
and 1 312 263 non zero values in the matrix.

Any help ?
Is it possible to handle glpk so that it minimises memory usage ?
Or should I think about another solver (which I don't want to!)

thanks,

Florent HERNANDEZ