Original Message:
Sent: Thu February 06, 2025 10:20 PM
From: Duc Duy Nguyen
Subject: CPLEX got stuck in "Performing restart"
Thank you very much, however, it does not work in my works.
Version identifier: 22.1.1.0 | 2022-11-27 | 9160aff4d
CPXPARAM_Preprocessing_RepeatPresolve 0
CPXPARAM_TimeLimit 600
Legacy callback pi
Tried aggregator 2 times.
Detecting symmetries...
MIP Presolve eliminated 80 rows and 40 columns.
Aggregator did 60 substitutions.
Reduced MIP has 2380 rows, 500 columns, and 10100 nonzeros.
Reduced MIP has 440 binaries, 0 generals, 0 SOSs, and 40 indicators.
Presolve time = 0.00 sec. (7.96 ticks)
Probing fixed 4 vars, tightened 48 bounds.
Probing changed sense of 1 constraints.
Probing time = 0.00 sec. (1.93 ticks)
Clique table members: 21.
MIP emphasis: balance optimality and feasibility.
MIP search method: dynamic search.
Parallel mode: deterministic, using up to 22 threads.
Root relaxation solution time = 0.02 sec. (6.55 ticks)
Nodes Cuts/
Node Left Objective IInf Best Integer Best Bound ItCnt Gap
0 0 57.0000 36 57.0000 20
0 0 57.0000 152 Cuts: 695 241
0 0 57.0096 94 Cuts: 464 460
0 0 65.6892 52 Cuts: 457 539
0 0 65.6892 73 Cuts: 463 685
* 0+ 0 5595.0000 65.6892 98.83%
Detecting symmetries...
0 2 65.6892 40 5595.0000 73.5712 685 98.69%
Elapsed time = 0.78 sec. (1295.70 ticks, tree = 0.02 MB, solutions = 1)
* 35+ 5 5531.0000 74.3151 98.66%
* 45+ 6 5479.0000 78.0279 98.58%
* 56+ 6 5467.0000 79.0000 98.55%
3208 2619 infeasible 5467.0000 79.0026 30514 98.55%
* 3855+ 2937 5404.0000 79.0026 98.54%
Performing restart 1
Repeating presolve.
Tried aggregator 1 time.
MIP Presolve eliminated 29 rows and 12 columns.
MIP Presolve modified 7620 coefficients.
Reduced MIP has 2351 rows, 488 columns, and 10039 nonzeros.
Reduced MIP has 434 binaries, 0 generals, 0 SOSs, and 34 indicators.
Presolve time = 0.02 sec. (6.16 ticks)
Tried aggregator 1 time.
Reduced MIP has 2351 rows, 488 columns, and 10039 nonzeros.
Reduced MIP has 434 binaries, 0 generals, 0 SOSs, and 34 indicators.
Presolve time = 0.00 sec. (5.02 ticks)
Represolve time = 0.02 sec. (14.32 ticks)
* 4911+ 0 5368.0000 79.0026 98.53%
4911 0 71.6481 90 5368.0000 Cuts: 442 54173 98.53%
4911 0 76.3176 31 5368.0000 Cuts: 262 54302 98.53%
4911 0 79.0196 106 5368.0000 Cuts: 366 54512 98.53%
* 4911+ 0 5355.0000 79.0196 98.52%
4911 0 80.0000 109 5355.0000 Cuts: 528 54621 98.51%
4911 0 81.0425 117 5355.0000 Cuts: 594 54817 98.49%
4911 0 83.0000 92 5355.0000 Cuts: 585 54923 98.45%
4911 0 85.0351 107 5355.0000 Cuts: 553 55087 98.41%
4911 0 86.5286 73 5355.0000 Cuts: 663 55197 98.38%
4911 0 86.5286 64 5355.0000 Cuts: 687 55273 98.38%
4911 0 86.5286 127 5355.0000 Cuts: 678 55461 98.38%
4911 0 86.5286 65 5355.0000 Cuts: 231 55531 98.38%
4911 0 86.5286 43 5355.0000 Cuts: 687 55606 98.38%
4911 0 86.5286 51 5355.0000 Cuts: 687 55699 98.38%
4911 0 86.5286 46 5355.0000 Cuts: 687 55775 98.38%
4911 0 86.5286 66 5355.0000 Cuts: 677 55865 98.38%
Repeating presolve.
Tried aggregator 2 times.
MIP Presolve modified 7600 coefficients.
Aggregator did 17 substitutions.
Reduced MIP has 2334 rows, 471 columns, and 10022 nonzeros.
Reduced MIP has 417 binaries, 0 generals, 0 SOSs, and 34 indicators.
Presolve time = 0.00 sec. (6.73 ticks)
Tried aggregator 1 time.
Reduced MIP has 2334 rows, 471 columns, and 10022 nonzeros.
Reduced MIP has 417 binaries, 0 generals, 0 SOSs, and 34 indicators.
Presolve time = 0.02 sec. (4.82 ticks)
Represolve time = 0.02 sec. (16.84 ticks)
.........................
------------------------------
Duc Duy Nguyen
Original Message:
Sent: Tue January 28, 2025 10:07 AM
From: Thierry Sola
Subject: CPLEX got stuck in "Performing restart"
Hello,
You can try the following:
read yourmodel.lp
write yourmodel.pre // write the presolve model
read yourmodel.pre
set preprocessing presolve n // not apply presolve
optimize
If necessary, you can save the solution and warmstart with it on the initial model.
write yourmodel.sol
read yourmodel.lp
read yourmodel.sol
set preprocessing presolve y
optimize
Regards,
------------------------------
Thierry Sola
Original Message:
Sent: Sun January 26, 2025 08:05 AM
From: Duc Duy Nguyen
Subject: CPLEX got stuck in "Performing restart"
I tried to solve an MILP model, and the time limit was 3600 s. However, CPLEX got stuck in "Performing restart"; it took more than 3600s, as I expected.
So what I want is the turn of performing restart, but there are no guidelines.
Thank you very much
Here is an engine log.
Version identifier: 22.1.1.0 | 2022-11-27 | 9160aff4d
CPXPARAM_TimeLimit 7200
Legacy callback pi
Tried aggregator 2 times.
MIP Presolve eliminated 60 rows and 31 columns.
Aggregator did 45 substitutions.
Reduced MIP has 1350 rows, 301 columns, and 5655 nonzeros.
Reduced MIP has 255 binaries, 0 generals, 0 SOSs, and 30 indicators.
Presolve time = 0.00 sec. (3.53 ticks)
Probing fixed 0 vars, tightened 30 bounds.
Probing time = 0.00 sec. (3.16 ticks)
Tried aggregator 1 time.
Detecting symmetries...
MIP Presolve eliminated 15 rows and 0 columns.
MIP Presolve modified 15 coefficients.
Reduced MIP has 1335 rows, 301 columns, and 5625 nonzeros.
Reduced MIP has 255 binaries, 0 generals, 0 SOSs, and 30 indicators.
Presolve time = 0.00 sec. (2.42 ticks)
Probing time = 0.00 sec. (2.15 ticks)
Clique table members: 15.
MIP emphasis: balance optimality and feasibility.
MIP search method: dynamic search.
Parallel mode: deterministic, using up to 22 threads.
Root relaxation solution time = 0.02 sec. (6.69 ticks)
Nodes Cuts/
Node Left Objective IInf Best Integer Best Bound ItCnt Gap
0 0 131.0000 154 131.0000 185
0 0 131.0434 64 Cuts: 431 295
0 0 134.4727 64 Cuts: 387 365
0 0 136.5750 31 Cuts: 375 425
* 0+ 0 767.0000 136.5750 82.19%
0 0 136.5750 50 767.0000 Cuts: 275 468 82.19%
0 0 136.5750 109 767.0000 Cuts: 118 603 82.19%
Detecting symmetries...
* 0+ 0 628.0000 136.5750 78.25%
* 0+ 0 627.0000 139.5000 77.75%
Detecting symmetries...
0 2 136.5750 109 627.0000 139.5000 603 77.75%
Elapsed time = 0.41 sec. (175.09 ticks, tree = 0.02 MB, solutions = 3)
* 1178+ 922 625.0000 143.0000 77.12%
* 2460 1706 integral 0 624.0000 143.0000 49975 77.08%
* 2943 1978 integral 0 619.0000 143.0000 55846 76.90%
3553 2626 357.0000 92 619.0000 143.0000 71057 76.90%
4671 3360 422.0000 44 619.0000 143.0000 94149 76.90%
4832 3276 292.0000 82 619.0000 143.0000 91953 76.90%
Performing restart 1
Repeating presolve.
Tried aggregator 1 time.
MIP Presolve modified 4200 coefficients.
Reduced MIP has 1335 rows, 301 columns, and 5625 nonzeros.
Reduced MIP has 255 binaries, 0 generals, 0 SOSs, and 30 indicators.
Presolve time = 0.00 sec. (3.34 ticks)
Tried aggregator 1 time.
Reduced MIP has 1335 rows, 301 columns, and 5625 nonzeros.
Reduced MIP has 255 binaries, 0 generals, 0 SOSs, and 30 indicators.
..............................................................................................................................
------------------------------
Duc Duy Nguyen
------------------------------