Team Exasol
Team Exasol

This article presents an overview of EXAStorage, which consists of the following: 


  • Volumes are partitioned into logical blocks
  • Blocks are distributed equally across all nodes/segments
  • Nodes may have segments of multiple volumes


  • A segment consists of (an arbitrary number of) partitions
  • Partitions may be distributed across (an arbitrary number of) disks
  • Blocks are distributed equally across all partitions

Block distribution

  • horizontal block distribution
    • More flexible
    • Application is responsible for handling parallelism
  • vertical block distribution (currently in use)
    • Maximum automatic parallelism
    • Parallelism is not handled by the application
    • Stripe size 1 (4K)
  • Version 6
    • Uses vertical block distribution with stripes (256K, stripe size 64)
    • DATA volumes must be recreated in version 6 to use this improvement