Over the past 6 months, it has become apparent to the team that:
- The availability of an ASIC for Cuckoo Cycle at launch is a distinct possibility.
- The current ASIC market is centralized, especially when it comes to recent cryptocurrency releases. The development of a competitive ASIC market takes time.
- A healthy and grassroot GPU mining community at launch is highly desirable.
After a significant amount of discussion, the Grin development team is proposing an update to its proof-of-work algorithm.
- Two proofs of work for the first 2 years (roughly): Cuckoo Cycle and Equihash.
- Equihash parameters are set to use around 7GB of memory, likely parameters are (108, 3). To avoid confusion with other parameters, we will refer to this as Equigrin.
- A multiplier is adjusted with the difficulty to maintain a constant ratio of blocks between Cuckoo and Equihash, on average.
- The ratio at launch should be 10% for Cuckoo, the rest for Equihash. This will smoothly transition to 100% Cuckoo over the next 2 years (roughly) by increasing the ratio by 1% every 12,000 blocks (about 8 days).
- If this solution is accepted, we will hard fork a tweak to Equihash every 6 months, with our planned hard forks, to deter stealth ASIC mining.
- After 2 years, Equihash will be abandoned and Grin will only have Cuckoo Cycle for proof-of-work.
Comments and thoughts are highly welcome! This will also be discussed tomorrow 8/27 at 15:00 UTC on Gitter, during our governance meeting.
P.S. If you’re reading this and plan on mining or investing in mining on grin, consider contributing to the latest funding campaign.
- Why not just Cuckoo? Cuckoo as it is now is very ASIC friendly. In the early days of Grin and as its mining market matures, we cannot expect full reliance on ASICs. A grassroot upstart with a more open distribution is also closer the Grin’s ethos. Finally, a mature ASIC market is needed to minimize centralization.
- Why not just Equihash? In the long term, ASICs can’t be prevented. We do not want to keep forking regularly, especially as the Grin mining market matures. Once only ASICs are profitable, Cuckoo is the simplest and optimal solution.
- But Equihash already has ASICs! Mostly for Zcash and because the Equihash parameters chosen require little memory (about 140MB). Grin’s flavor of Equihash, Equigrin, should require at least 7GB. This increases the cost of ASIC production and obsoletes some of the larger GPU mining farms (i.e. NiceHash). In addition, we will tweak some Equihash parameters every 6 months to obsolete any ASIC development.
- Why not ProgPOW instead of Equihash? For 2 main reasons: 1) Equihash remains a lot simpler 2) ProgPOW places an additional burden on proof-of-work verification making it less suited to light environments (cell phones, small VPCs, etc).
- Why not Equigrin only for 2 years, followed by Cuckoo Cycle We do want a Cuckoo Cycle ASIC market to emerge gradually. This is the optimal (and unavoidable) long term option. The 2 years period should allow a gradual transition from a grassroot GPU market to a mature ASIC market.