An empirical guide to the behavior and use of scalable persistent memory
An empirical guide to the behavior and use of scalable persistent memory, Yang et al., FAST’20
We’ve looked at multiple papers exploring non-volatile main memory and its implications (e.g. most recently ‘Efficient lock-free durable sets‘). One thing they all had in common is an evaluation using some kind of simulation of the expected behaviour of NVDIMMs, because the real thing wasn’t yet available. But now it is! This paper examines the real-world behaviour of Intel’s Optane DIMM, and finds that not all of the assumptions baked into prior works hold. Based on these findings, the authors present four guidelines to get the best performance out of this memory today. Absolutely fascinating if you like this kind of thing!
The data we have collected demonstrate that many of the assumptions that researchers have made about how NVDIMMs would behave and perform are incorrect. The widely expressed expectation was that NVDIMMs would have behavior that was broadly similiar to DRAM-based DIMMs but with lower performance (i.e., higher latency and lower bandwidth)… We have found the actual behavior of Optane DIMMs to be more complicated and nuanced than the "slower, persistent DRAM" label would suggest.











