1. A microprocessor into a memory chip Dave Patterson, Berkeley, 1997
Intelligent RAM
A microprocessor into a memory chip
Dave Patterson, Berkeley, 1997

2. Context Distinct manufacturing lines Processor-Memory performance gap
Memory wall
Awkwardness of DRAM chips
Time to unify logic and memory

3. Advantages Higher bandwidth and lower latency Less energy consumption
Less distance (no bus) and less complexity
Less energy consumption
Less heat, better performance
Costs efficient
Save board space

4. Disadvantages Consequences on cost/bit and refresh rate
Manufacturing challenges
Reduce interchangeability
ILP trade-off

5. VIRAM 2 2 2 2 2 2 2 2

6. Microarchitecture

7. Results
Multiple operations can execute concurrently across parallel lanes
High performance
but
Not efficient with short vectors
Useless for non-vectorizable parallelism

8. Conclusion VIRAM / DIVA not real successes
but implications in embedded systems
Intel : Through Silicon Vias, personal technology to connect DRAM and processor
First step to IRAM ?