# Verkle Open Questions
1. **✅ ~~Selfdestruct~~**
- Current plan: EIP-6780 is CFI’d for [Cancun](https://eips.ethereum.org/EIPS/eip-6780)
- See [impact audit](https://docs.google.com/document/d/1HDbym5YOoYj63xswMAwvt5Psh4JaI0biY06b6ZvYV2s/edit) completed by Dedaub
1. **Migration method**
- Current top candidate: Overlay Method (see Pari’s [writeup](https://notes.ethereum.org/@parithosh/verkle-transition#%E2%80%9COverlay%E2%80%9D-live-conversion-method))
- Guillaume has a working proof-of-concept 🎉
- [Implementation questions](https://notes.ethereum.org/bdfbEEf6QcypV0Cv8dlqBw?view)
- TBD: performance with more recent blocks
1. **Preimage distribution**
- [EIP opened](https://github.com/ethereum/EIPs/pull/6873) to enable preimage recording starting prior to the verge
- But still need a way to distribute historical preimages
- Strong preference: distribute them over the p2p network
- Other options: can use a system of CDNs similar to checkpoint sync, or use snap sync? (Perhaps less important where users actually get the preimage from, as long as it’s easy to verify)
1. **Verkle snap sync**
- Tanishq has a working proof-of-concept
- Next step: implement stateless version so it can be tested on Kaustinen.
- Tanishq to share a summary of the way Verkle Sync works currently, and list of known problems.
3. **Witness size estimates / block size estimates post-Verkle**
1. **Block processing times (Verkle vs MPT)**
- Performance of replaying blocks compared to MPT
- Last benchmark: ~40% overhead
- TBD: performance with more recent blocks
1. **Gas schedule changes**
1. **Other areas in need of discussion, test coverage, etc:**
- Reorgs, JSON-RPC, mainnet-like blocks, mainnet shadow fork