# adjustment_interval (/docs/hyperparameters/adjustment-interval) Historically the cadence of Bittensor's registration-price controller: every `adjustment_interval` blocks, the chain compared registrations against [`target_regs_per_interval`](/docs/hyperparameters/target-regs-per-interval) and moved the burn cost and PoW difficulty up or down. It matters today mostly as context — the current chain adjusts the burn price continuously instead. ## How it works [#how-it-works] The parameter lives in `AdjustmentInterval` storage (u16 block count, default 100 blocks ≈ 20 minutes, from `SubtensorInitialAdjustmentInterval` in `runtime/src/lib.rs`). In the current runtime, however, **no adjustment logic reads it**: the interval-based controller was replaced by a per-block mechanism in `pallets/subtensor/src/subnets/registration.rs` where each registration multiplies the burn by [`burn_increase_mult`](/docs/hyperparameters/burn-increase-mult) and the price decays every block with half-life [`burn_half_life`](/docs/hyperparameters/burn-half-life), clamped to \[[`min_burn`](/docs/hyperparameters/min-burn), [`max_burn`](/docs/hyperparameters/max-burn)]. The value is still stored, returned by the `subnet_hyperparameters` query, and settable — the extrinsic (`sudo_set_adjustment_interval` in `pallets/admin-utils/src/lib.rs`) checks only that the subnet exists — but changing it has no effect on registration pricing. Even the root subnet's per-interval registration counter resets on the root epoch boundary (`tempo`), not on this interval. The chart below replays the same registration burst under the old once-per-interval controller and the current per-block one — drag the interval to see what the cadence used to change. ## Reading and setting [#reading-and-setting] ```bash btcli sudo get --netuid 12 --name adjustment_interval ``` Root/governance only — `sudo_set_adjustment_interval` requires the root origin, so subnet owners cannot change it. The value is a plain block count (12-second blocks). ## Related [#related] * [`burn_half_life`](/docs/hyperparameters/burn-half-life) — the cadence's replacement for burn decay * [`burn_increase_mult`](/docs/hyperparameters/burn-increase-mult) — the per-registration response * [`adjustment_alpha`](/docs/hyperparameters/adjustment-alpha) — the smoothing factor of the same legacy controller * [`target_regs_per_interval`](/docs/hyperparameters/target-regs-per-interval)