[Help-glpk] Out of memory, malloc error

[Anthony Presley]

All:

We have a (what I consider) to be fairly simple model, which performs
very well for small - medium data sets (between 500 and 2500 lines of
data).  However, we recently tried to use the mod file for a larger data
set (about 3200 lines of data).  Note: We're not using glpk to solve our
Integer Program, we use it to create an MPS file, which is then solved
by another solver, so we use the --check option.  Using this method, we
have an MPS file generated in under 20 seconds.

Using a faster Core 2 Duo, 2GB of RAM, and 2GB of swap, glpk ran fine
until our last rule.  In the last rule, memory sky rocketed from 400MB
for the glpk process to more than 4GB, resulting in a system load of
over 20, and glpk eventually quit with a malloc() error.  It took over
60 minutes to get to this point.

So, I moved it to our production system, which has 4GB of RAM and 4GB of
swap, and the same thing occurred.  It took over 40 minutes to get to
this point.

Our original data sets use about 200 - 300MB, in total.

Any ideas on how we might go about speeding up the creation of the MPS
file .... and bringing down the memory footprint?


Thanks.


--
Anthony