Originally posted by: SystemAdmin

Hey Guys! First: as I'm a new user of cplex, i'm also new to this forum. Please be kind ;)

Here's my problem:

I have a relatively large lp file (have a look at the attachment :) containing an MIP problem i wish to optimize.
Unfortunately i can't figure out, how to achieve this. When i start the optimization, the cplex binary forks into some threads using all available kernels, does a lot of workload and finally falls asleep.

htop shows a number of cplex processes with no cpu load, stating sleep mode (S) for those processes.

here's the commands i use to start cplex:

#>cplex
set logfile problem.log
set workmem 512
read <nameoftask>.lp
optimize

of course, <nameoftask> is replaced by the correct filename.

i also tried to alternate parameters like "set mip cuts all 2", "set mip cuts covers 3" and "set mip cuts disjunctive 3", but none of this helps.

any clues?

i'm running cplex under Debian 4.4.4-7 on different 64bit machines with up to eight kernels.

cheers,
0perat0r
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: SystemAdmin

i forgot to say: i'm running IBM(R) ILOG(R) CPLEX(R) Interactive Optimizer 12.2.0.0.
Attached you find the log file related to the problem file above...
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#DecisionOptimization

Originally posted by: SystemAdmin

Are you saying that you have repeatedly seen CPLEX going into a deadlock for this model with different parameter settings? This is very strange. Maybe you should first try the most recent CPLEX version, which is 12.3.

Tobias
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#DecisionOptimization