This article presents an overview of EXAStorage, which consists of the following:
Volumes
- Volumes are partitioned into logical blocks
- Blocks are distributed equally across all nodes/segments
- Nodes may have segments of multiple volumes
Segments
- 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
