pub const SHIELDED_IDENTITY_TOP_UP_BALANCE_STORAGE_BYTES: u64 = 8;Expand description
Flat component (in effective bytes at the per-byte storage rate) for the identity-side write an
IdentityTopUpFromShieldedPool performs on top of its per-action nullifier and note writes:
the single AddToIdentityBalance operation, charged as part of the pool-paid flat fee (built
like SHIELDED_UNSHIELD_ADDRESS_STORAGE_BYTES).
What the write does: the identity must already exist, so it adds no storage. It rewrites the
balance element and every Merk node on the path to the root (replaced bytes, charged at the
per-byte processing rate), loads the path, seeks, and rehashes the nodes. Measured at protocol
version 14: 320 replaced bytes, 886 loaded bytes, 12 seeks and 14 hash calls for 175,320
credits of processing. Like every other flat shielded component, that variable tree work is
folded into one flat effective-byte figure priced at the full storage rate so it tracks the
rate as it evolves, rather than modelled per replaced byte: 175,320 credits is 6.4 effective
bytes at 27,400 credits/byte, and 8 leaves headroom for the path growing by about a node
(roughly 0.7 effective bytes) each time the identity count doubles. The pool-total update is
not priced separately, exactly as for the other pool-paid transitions. See
compute_minimum_shielded_fee::compute_shielded_identity_top_up_fee.