What’s in this document?

Minimum requirements

The minimum requirements allow loading datasets only up to 50 million RDF triples.

  • 2 GB Memory
  • 2 GB Disk space
  • Java SE Development Kit 8 (optional for GraphDB Free desktop installation)


All GraphDB indexes are optimized for hard disk with very low seek time. Our team highly recommend using only SSD partition for persisting repository images!

Hardware sizing

The best approach to correctly size the hardware resources is to estimate the number of explicit statements. Statistically, an average dataset has 3:1 statements to unique RDF resources. The total number of statements determines the expected repository image size and the number of unique resources affects the memory footprint required to initialise the repository.

The table below summarises the recommended parameters for planning RAM and disk sizing:

  • Statements are the planned number of explicit statements.
  • Unique resources are the expected number of unique RDF resources (IRIs, blank nodes, literals).
  • Java heap (minimal) is the minimal recommend JVM heap required to operate the database controlled by -Xmx parameter.
  • Java heap (optimal) is the recommended JVM heap required to operate a database controlled by -Xmx parameter.
  • Off heap is the database memory footprint (outside of the JVM heap) required to initialise the database.
  • OS is the recommended minimal space reserved for the operating system.
  • Total is the RAM required to provide for the hardware configuration.
  • Repository image is the expected size on disk. For repositories with inference use the total number of explicit + implicit statements.
Statements Unique resources Java heap (min) Java heap (opt) Off heap OS Total Repository image
100M 33.3M 1.2GB 3.6GB 370M 2 6GB 12GB
200M 66.6M 2.4GB 7.2GB 740M 3 11GB 24GB
500M 166.5M 6GB 18GB 1.86GB 4 24GB 60GB
1B 333M 12GB 30GB 3.72GB 4 38GB 120GB
2B 666M 24GB 30GB 7.44GB 4 42GB 240GB
5B 1.665B 30GB 30GB 18.61GB 4 53GB 600GB
10B 3.330B 30GB 30GB 37.22GB 4 72GB 1200GB
20B 6.660B 30GB 30GB 74.43GB 4 109GB 2400GB


GraphDB Free is available under an RDBMS-like free license. It is free to use but not open-source. Before redistributing GraphDB Free, please contact us at to receive a permission.