deepest
what it holds
Deepest holds the longest single stall the record has ever proven, measured in fast blocks. It is one interval, not a sum, and it stands for a stretch of production during which the settlement clock did not move.
Three values are stored together.1 The length, the slow block the chain hung on for the duration, and the address that was present when the interval closed.
The address is recorded because the field is a claim someone stood behind. It carries no privilege, no balance and no standing beyond appearing in this row.
Until an interval closes with a length greater than the current value, all three parts stay exactly as they were.
what writes it
It is written only when a newly closed interval exceeds the current value. The comparison happens inside the same call that closes the interval, and it is a single comparison against a single stored number.
The write replaces all three parts at once. There is no partial succession in which a length is kept and an address is not.
Nothing else replaces it. No decay, no reset at a band boundary, no expiry after a period of quiet, and no instruction that clears the field.1
An interval closed by a lapse can also take the field, provided its proven length is greater than the value standing.
what it cannot do
Deepest is the one field that is a claim about the chain rather than about the record. Every other field describes what was read; this one describes what happened out there.
It cannot describe stalls nobody was present for. A longer stall may have occurred and left no trace, and the field has no way to represent that possibility.
It cannot be lowered. Even where a later reading suggests the interval was shorter than recorded, nothing in the contract acts on that suggestion.
It cannot be attributed to the chain as a fault. The record states the length and stops there.
how to read it
A deepest that has not moved in a long time admits two readings. Either the chain has settled cleanly throughout that stretch, or nobody was there for the stall that would have beaten it.
The two are not distinguishable from this field alone.1 Read it beside dark and beside the mark register, and the ambiguity narrows.
A deepest that moves often says the record is being attended during the periods that matter, since only a present observer can produce a new one.
The succession table lists every value the field has held, so the history is legible even though only the current value is stored as the field.
| value | slow block | witness | superseded at |
|---|---|---|---|