Struct Parameters 

pub struct Parameters {

    pub db_path: PathBuf,
    pub leader_timeout: Duration,
    pub min_block_delay: Duration,
    pub soft_leader_timeout: Duration,
    pub block_rate_window: Duration,
    pub max_headers_per_commit_sync_fetch: usize,
    pub max_transactions_per_commit_sync_fetch: usize,
    pub max_headers_per_header_sync_fetch: usize,
    pub max_transactions_per_transaction_sync_fetch: usize,
    pub sync_last_known_own_block_timeout: Duration,
    pub dag_state_cached_rounds: u32,
    pub peer_round_ahead_margin: u32,
    pub commit_sync_parallel_fetches: usize,
    pub commit_sync_batch_size: u32,
    pub commit_sync_batches_ahead: usize,
    pub commit_recovery_batch_size: u32,
    pub max_headers_per_bundle: usize,
    pub max_shards_per_bundle: usize,
    pub tonic: TonicParameters,
    pub fast_commit_sync_batch_size: u32,
    pub commit_sync_gap_threshold: u32,
    pub enable_fast_commit_syncer: bool,
    pub enable_starfish_speed_adaptive_acknowledgments: bool,
    pub enable_peer_responsiveness_ranking: bool,
    pub dag_visualizer_port: Option<u16>,
}

Operational configurations of a consensus authority.

All fields should tolerate inconsistencies among authorities, without affecting safety of the protocol. Otherwise, they need to be part of IOTA protocol config or epoch state on-chain.

NOTE: fields with default values are specified in the serde default functions. Most operators should not need to specify any field, except db_path.

Fields

db_path: PathBuf

Path to consensus DB for this epoch. Required when initializing consensus. This is calculated based on user configuration for base directory.

leader_timeout: Duration

Time to wait for parent round leader before sealing a block, from when parent round has a quorum.

min_block_delay: Duration

Sustained spacing between own blocks: long-run production never exceeds one block per min_block_delay. This avoids generating too many rounds when latency is low. This is especially necessary for tests running locally. If setting a non-default value, it should be set low enough to avoid reducing round rate and increasing latency in realistic and distributed configurations.

soft_leader_timeout: Duration

Soft counterpart of leader_timeout: after this duration we are willing to propose a block even without a strong-vote quorum, to avoid liveness stalls when leader data is slow to propagate. Fires earlier than leader_timeout and does not force block creation on its own.

block_rate_window: Duration

Window bounding own block production together with min_block_delay: idle time accrues budget for bursts of up to block_rate_window / min_block_delay back-to-back blocks, letting a validator that fell behind catch up on rounds instead of skipping them. Set at or below min_block_delay to disable bursting (fixed spacing between blocks).

max_headers_per_commit_sync_fetch: usize

Number of block headers to fetch per commit sync request.

max_transactions_per_commit_sync_fetch: usize

Number of transactions to fetch per commit sync request.

max_headers_per_header_sync_fetch: usize

Number of block headers to fetch per header sync (periodic or live) request.

max_transactions_per_transaction_sync_fetch: usize

Number of transactions to fetch per transaction sync request.

sync_last_known_own_block_timeout: Duration

Time to wait during node start up until the node has synced the last proposed block via the network peers. When set to 0 the sync mechanism is disabled. This property is meant to be used for amnesia recovery.

dag_state_cached_rounds: u32

The number of rounds of blocks to be kept in the Dag state cache per authority. The larger the number the more the blocks that will be kept in memory allowing minimising any potential disk access. Value should be at minimum 50 rounds to ensure node performance, but being too large can be expensive in memory usage.

peer_round_ahead_margin: u32

Rounds a header from a far-future-bounded source may lead the locally accepted frontier, in addition to dag_state_cached_rounds, before it is dropped as too far ahead to connect.

commit_sync_parallel_fetches: usize

commit_sync_batch_size: u32

commit_sync_batches_ahead: usize

commit_recovery_batch_size: u32

Maximum number of commits scanned and replayed per batch during recovery, bounding peak memory when a large unprocessed range is replayed at startup.

max_headers_per_bundle: usize

Maximum number of headers to be included in a bundle. Headers exceeding the max allowed limit will be truncated.

max_shards_per_bundle: usize

Maximum number of transaction shards to be included in a bundle. Shards exceeding the max allowed limit will be truncated.

tonic: TonicParameters

Tonic network settings.

fast_commit_sync_batch_size: u32

commit_sync_gap_threshold: u32

enable_fast_commit_syncer: bool

Enable FastCommitSyncer for faster recovery from large commit gaps. Enabled by default; operators can disable it locally if bugs are discovered.

enable_starfish_speed_adaptive_acknowledgments: bool

Enable adaptive acknowledgment filtering for StarfishSpeed. Local heuristic that drops acks for authorities persistently blamed by recent strong-vote masks. Effective only when the protocol-level consensus_starfish_speed flag is also on. Enabled by default; operators can disable it locally without a protocol change.

enable_peer_responsiveness_ranking: bool

Prefer more responsive peers when the transactions synchronizer selects peers to fetch from. Ranking is a preference within the already-eligible candidate set, not a change of eligibility, so it cannot affect safety. Enabled by default; disabling it restores the previous selection: a uniform random order that excludes the most recently failed peers (up to less than f+1 by stake).

dag_visualizer_port: Option<u16>

Port for the DAG visualizer gRPC server (localhost only). When set, starts a debugging server for real-time DAG visualization. Only has an effect when the dag-visualizer feature is compiled in. Disabled by default (None).

Implementations

impl Parameters

pub fn unhandled_commits_threshold(&self) -> u32

Threshold for the number of commits sent to the consumer but not yet handled, above which commit producers (commit syncers, commit observer recovery) pause to let the consumer catch up.

pub fn block_rate_burst(&self) -> u64

Burst capacity: maximum number of own blocks within block_rate_window (40 in production, 5 in msim, 8 in tests with the default window).

pub fn far_future_round_ceiling(&self, frontier: u32) -> u32

Highest round a header from a far-future-bounded source may have, relative to the accepted frontier, to still be close enough to connect; headers above this are too far ahead and dropped.

pub fn max_headers_per_fetch(&self, commit_sync: bool) -> usize

Maximum number of block headers served per fetch request, depending on whether the request comes from commit sync or the header synchronizer.

pub fn validate(&self) -> Result<(), String>

Validates local consensus parameters, rejecting zero values that can lead to synchronization problems. Returns a description of the first offending field.

Trait Implementations

impl Clone for Parameters

fn clone(&self) -> Parameters

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Parameters

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Parameters

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Parameters

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Parameters

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.