Skip to content

Sintef2008 (VRPTW)

Sintef2008 is the MAMUT-routing curation of the most classical VRPTW benchmark convention. The instances themselves come from Solomon 1987, for the original 100-customer instances (and their derived smaller 25 and 50-customer variants), and from Gehring and Homberger 1999, for larger instances up to 1000 customers. These instances have been the reference workload for VRPTW research for decades. They define the usual R, C, and RC families, respectively random, clustered, and mixed customer distributions, with type-1 and type-2 variants reflecting tighter/shorter versus looser/longer TW scheduling structures.

The Sintef2008 convention is not merely an instance collection: it is an evaluation contract. It uses Euclidean distances as arc costs, computed with double-precision floating point arithmetic, and a hierarchical objective: first minimize the number of vehicles (equivalently the number of non-empty routes), then break ties by minimizing total travel cost. This is the historical Solomon/SINTEF convention used by most metaheuristic papers reporting "best-known solutions" on the classical VRPTW.

In 2008, SINTEF proposed its VRPTW benchmark website as a curated scoreboard for the Solomon and Gehring--Homberger instances. This was an important step towards standardization: researchers could retrieve instances, inspect BKS values, and submit improvements through a single institutional reference. SINTEF reports objective values rounded to two decimals, while explicitly specifying that the underlying distance evaluation uses float64, i.e., double-precision floating point arithmetic.

Though this benchmark became a cornerstone for VRPTW research, it remains perfectible. Issues include the still heavily manual-script work required to collect instances with their BKS from the website, several BKS values have historically been disputed because of rounding, scaling, or slightly different evaluation conventions. Some entries have objective values without machine-checkable route files, and improvements still rely on communication with a centrally maintained, non-open-source website. This creates a bottleneck: the community depends on a private institutional scoreboard for data that has become scientific infrastructure.

The MAMUT-routing Sintef2008 family consolidates the SINTEF benchmark with alternative BKS sources such as Combopt, CVRPLib BKS kindly provided by Eduardo Queiroga through personal communication and Czech personal website. The curated artifacts expose machine-readable instance files, BKS route files, objective-function metadata, and checker-compatible JSON. We also impose a deterministic route ordering, by sorting routes according to their first customer ID, so that route files and floating-point aggregation are reproducible across runs and formats.

Licensing note: MAMUT-routing-authored curation artifacts for this family are distributed under the MIT License where MAMUT-routing holds the relevant rights. The underlying historical benchmark definitions and some BKS sources remain third-party benchmark material and are not relicensed by this curation.

The family currently contains the 468 classical VRPTW instances over 8 different instance sizes, each with a HierarchicalVehicleCost BKS.

May 2026 note. The CVRPlib now also exposes its own VRPTW benchmark (previously unavailable through their website) built on the same Solomon and Gehring--Homberger instances, but under the DIMACS convention: a mono-cost objective over scaled, integerized arc costs (see Dimacs2021 below). As such, their collection differs from our curated Sintef2008 benchmark family since we respect the original hierarchical objective and floating-point costs, whereas cost-only integerized variants belong to a different benchmark contract.

Data

Instances and best-known solutions: /benchmarks/vrptw/sintef2008/ on the website. Repository: https://github.com/ANR-MAMUT/MAMUT-routing/tree/main/benchmarks/VRPTW/Sintef2008.

Repository README

Sintef2008 benchmark family

This directory contains the MAMUT-routing curation of the classical Solomon/Gehring-Homberger VRPTW instances under the SINTEF 2008 hierarchical objective convention.

License scope:

  • MAMUT-routing-authored curation artifacts, normalized metadata, and contributed files are distributed under MIT where MAMUT-routing holds the relevant rights.
  • The underlying benchmark definitions and some BKS sources originate from third-party historical benchmark material. This directory-level notice does not relicense those third-party sources.

Preserve this README, this directory's LICENSE file, and the repository NOTICE when redistributing this benchmark family.