1. AI/ML as the primary driver for compute‑in‑memory
Many commenters see the main benefit of putting processing inside RAM as accelerating AI inference, which reduces to repetitive, low‑precision matrix operations.
- “AI inference is basically 1 operation iterated over every single model weight. That's what's makes computer in memory attractive and feasible.” – MadnessASAP
- “Many algorithms can be reasonably converted into matmul. Not many algorithms can be reasonably converted into very low precision matmul. And that's all that these things are going to do.” – Tuna‑Fish
- “Integrated RAM with tensor processing seems like the end game for silicon that's actually efficient at running AI models.” – api
2. Practical adoption barriers (cost, software, niche use)
Several participants argue that adding compute to DRAM will raise costs and require software support, limiting it to specialized niches rather than mainstream DIMMs.
- “Adding compute to memory will make it more expensive, so it will get zero adoption outside of the niches where it actually proves to be useful and valuable.” – wtallis
- “The problem is that you need to get software support for it. Arguably easier these days with open source but still doesn't magically happen.” – ghaff
3. Historical context and prior attempts
The idea of processor‑in‑memory is not new; past research (e.g., computational RAM from 1998, HBM5, Hybrid Memory Cube) faced similar challenges and offers lessons for current proposals.
- “Processor‑in‑Memory ... was even explored in a doctoral thesis from 1998: Computational RAM: A Memory‑SIMD Hybrid. … At the time, the motivation was … hundreds of gigabytes (terabits) of bandwidth available inside the memory chip … The author pushed it to the extreme where there was a wide array of 1‑bit processors at each column of DRAM.” – roadbuster
- “The designers of HBM5 had the same observations … but … this is almost exactly what Intel and Micron pitched 15 years ago as Hybrid Memory Cube … which lost on the market compared to the simpler, less costly, and more flexible alternative, HBM.” – roadbuster