Begin-Block

Each abci begin block call, the historical info will get stored and pruned according to the HistoricalEntries parameter.

Historical Info Tracking

If the HistoricalEntries parameter is 0, then the BeginBlock performs a no-op.

Otherwise, the latest historical info is stored under the key historicalInfoKey|height, while any entries older than height - HistoricalEntries is deleted. In most cases, this results in a single entry being pruned per block. However, if the parameter HistoricalEntries has changed to a lower value there will be multiple entries in the store that must be pruned.