Erigon 3: Prune canonical markers - CanonicalHash, HeaderNumber from chaindata

[Giulio2002]

We prune CanonicalHash and HeaderNumber in chaindata. this leads to a -99% in these 2 tables and reduce their total size to 40 pages in TOTAL (from >500k pages).

Benchmarks:

Total time taken to query blocks from 1000000 to 3000000: 1720.1410 seconds (OLD)
Total time taken to query blocks from 1000000 to 3000000: 1747.4729 seconds (New)

Amortized delta cost: 0.1ms/req

Is the RPC working for those ranges? Yes.

How does it work?

Query canonical hash from snapshots by: viewHeaderByNumber -> header.Hash() if db hit is missed
Query header number from snapshots by: viewHeaderByHash -> header.Num64 if db hit is missed

[Giulio2002]

• Add new methods to Ethbackend for CanonicalHash and HeaderNumber interfaces#227