Transactions

trim-null-subnet-batch

Execute one bounded Null subnet pruning batch toward `target`.

Cancels pending weight commits before moving UIDs, then removes at most the runtime's batch size (currently 64). A large legacy commit backlog can produce a cleanup-only batch. Read NullPruningTarget and SubnetworkN after inclusion: a successful transaction does not imply the final target has been reached. Continue with the same target until the pending target is absent. Each batch is owner-authorized and respects the admin freeze window. Only the first batch starts the trimming cooldown; changing the target is a new operation. Survivor UID values can change.

Signer	Origin	Pallet	Wraps
`coldkey`	subnet owner	AdminUtils	`AdminUtils.sudo_trim_null_uids_batch`

Parameters

Parameter	Type	Required	Description
`netuid`	integer	yes	Null subnet owned by the signer.
`target`	integer	yes	Final UID count, shared by every continuation.

Address parameters (--hotkey, --coldkey, --dest, ...) accept a raw ss58 address, an address-book or proxy-book name, or a local wallet/hotkey name.

CLI

Preview with --dry-run (shows fee, effects, and policy result without submitting), then submit:

btcli tx trim-null-subnet-batch \
  --netuid <int> \
  --target <int> --dry-run
btcli tx trim-null-subnet-batch \
  --netuid <int> \
  --target <int> -w my_coldkey

Python

import bittensor as bt
from bittensor.wallet import Wallet

wallet = Wallet(name="my_coldkey", hotkey="my_hotkey")
intent = bt.TrimNullSubnetBatch(netuid=1, target=64)

sub = bt.Subtensor()
plan = sub.plan(intent, wallet)   # fee, effects, policy — no submission
result = sub.execute(intent, wallet)
if not result.success:
    print(result.error.code, result.error.remediation)

(bt.Subtensor is also the async client — async with bt.Subtensor() as client: — see The client.) Or build the intent by op name, as an agent would:

result = sub.execute_tool("trim_null_subnet_batch", {...}, wallet)

On-chain implementation

AdminUtils.sudo_trim_null_uids_batch — pallets/admin-utils/src/lib.rs#L2138:

#[pallet::call_index(112)]
#[pallet::weight(<T as pallet::Config>::WeightInfo::sudo_trim_null_uids_batch().max(<T as pallet::Config>::WeightInfo::sudo_trim_null_uids_batch_many_mechanisms()))]
pub fn sudo_trim_null_uids_batch(
    origin: OriginFor<T>,
    netuid: NetUid,
    target: u16,
) -> DispatchResult {
    let continuing = pallet_subtensor::NullPruningTarget::<T>::get(netuid) == Some(target);
    let limits: &[TransactionType] = if continuing {
        &[]
    } else {
        &[TransactionType::MaxUidsTrimming]
    };
    let maybe_owner = pallet_subtensor::Pallet::<T>::ensure_sn_owner_or_root_with_limits(
        origin, netuid, limits,
    )?;
    pallet_subtensor::Pallet::<T>::ensure_admin_window_open(netuid)?;
    pallet_subtensor::Pallet::<T>::trim_null_uids_batch(netuid, target)?;
    if !continuing {
        pallet_subtensor::Pallet::<T>::record_owner_rl(
            maybe_owner,
            netuid,
            &[TransactionType::MaxUidsTrimming],
        );
    }
    Ok(())
}

Every file is browsable under /code exactly as built into the runtime, or as plain text under /code/raw/<path> (index: /code/index.json).