Single-system image
From Wikipedia, the free encyclopedia
Single-system image or SSI is when the Operating System maintains its state as a single copy of data in memory. Each system call on a processor can obtain data by load/store to that single copy. For example, a system that has an individual boot disk that operates using 1, 2, 512 or more processors.
Another suggested definition is a form of distributed computing in which by using a common interface multiple networks, distributed databases or servers appear to the user as one system. In other words, the operating system environment is shared by all nodes in the system.
The following are examples of SSI clustering systems:
- Amoeba (inactive)
- The long-term goal of DragonFly BSD
- Genesis
- Inferno
- Kerrighed
- Nomad (inactive)
- OpenSSI
- Open-Sharedroot - shared root Cluster from ATIX
- Plan 9
- Plurix
- Sprite (inactive)
- Hewlett-Packard's TruCluster
- OpenVMS
Other clustering systems may provide certain SSI characteristics without appearing as a single virtual system:
