And the emulator tracks whether you've done the things mentioned in the article, like open a particular control panel or tried a particular menu option.

This is amazing.

  | Metric               | DiceDB   | Redis    |
  | -------------------- | -------- | -------- |
  | Throughput (ops/sec) | 15655    | 12267    |
  | GET p50 (ms)         | 0.227327 | 0.270335 |
  | GET p90 (ms)         | 0.337919 | 0.329727 |
  | SET p50 (ms)         | 0.230399 | 0.272383 |
  | SET p90 (ms)         | 0.339967 | 0.331775 |

Something I still fail to understand is where you can actually spend 20ms while answering a GET request in a RAM keyvalue storage (unless you implement it in Java).

I never gained much experience with existing opensource implementations, but when I was building proprietary solutions at my previous workplace, the in-memory response time was measured in tens-hundreds of microseconds. The lower bound of latency is mostly defined by syscalls so using io_uring should in theory result in even better timings, even though I never got to try it in production.

If you read from nvme AND also do the erasure-recovery across 6 nodes (lrc-12-2-2) then yes, you got into tens of milliseconds. But seeing these numbers for a single node RAM DB just doesn't make sense and I'm surprised everyone treats them as normal.

Does anyone has experience with low-latency high-throughput opensource keyvalue storages? Any specific implementation to recommend?

what would you recommend if someone wanted to go from nothing (maybe some softw. experience) to be able to do a hardware design like this? Is there any book/courses you consider to be a must?