MIPLIB Benchmark Records

Local-MIP establishes 10 new records on challenging MIPLIB open instances, demonstrating state-of-the-art performance through its novel local search operators and two-mode architecture.

Overview

MIPLIB is the standard benchmark library for evaluating mixed integer programming solvers, maintained by the optimization community at miplib.zib.de.

Open instances are the most challenging problems in MIPLIB, those for which the optimal solution has not yet been proven. Local-MIP’s records on these instances showcase the effectiveness of its local search approach on problems where traditional branch-and-bound methods struggle.

New Best-Known Solutions

The following table presents the 10 MIPLIB open instances where Local-MIP has established new best-known solutions, as reported in our AIJ 2025 paper.

All instances come from the MIPLIB 2017 open set, and all objectives are minimization problems (larger negative values indicate better solutions).

Instance Name Variables Constraints Constraint Types Previous Best Local-MIP
sorrell7 2,048 78,848 variable bound -196 -197
genus-sym-g31-8 3,484 32,073 knapsack, etc. -21 -23
supportcase22 7,129 260,602 mixed binary, etc. N/A† 117
cdc7-4-3-2 11,811 14,478 set packing -289 -294
genus-sym-g62-2 12,912 78,472 set partitioning, etc. -34 -38
genus-g61-25 14,380 94,735 cardinality, etc. -34 -40
ns1828997 27,275 81,725 precedence, etc. 9 8
neos-4232544-orira 87,060 180,600 aggregations, etc. 17,540,506.0 15,108,527.5
scpm1 500,000 5,000 set covering 554 544
scpn2 1,000,000 5,000 set covering 501 490

† First-ever feasible solution found for this instance.

  • MIPLIB Website - Official MIPLIB benchmark library
  • Papers - Publications describing Local-MIP’s algorithms
  • Software - Get Local-MIP to try on MIPLIB instances
  • Tutorials - Learn how to use Local-MIP
← Back to Home Papers Tutorials