MIMD: Shared-memory vs. message-passing
Single shared-address space (extension of uniprocessor)
- UMA: uniform memory access (centralized; shared-bus)
- NUMA: non-uniform memory access (decentralized “distributed shared-memory”; interconnection network)
- NUMA-CC: cache coherent (directory-based protocols)
- NUMA without cache coherence (enforced by software)
- Clusters
Processors communicate by messages (send, receive)
- Multicomputers (message-passing paradigm
- Synchronous (e.g. RPC) vs. asynchronous (sender does not wait for reply)