Configuration

Config is a plain struct with public fields. Defaults come from Config::new(node_id, peers).

#![allow(unused)]
fn main() {
let mut config = Config::new(node_id, peers);
config.election_timeout_min_ticks = 10;
config.election_timeout_max_ticks = 20;
config.heartbeat_interval_ticks = 3;
config.tick_interval = Duration::from_millis(50);
}

Timing

Field	Default	Note
`election_timeout_min_ticks`	10	§5.2 minimum election timeout.
`election_timeout_max_ticks`	20	Exclusive. Actual timeout is uniform in `[min, max)`.
`heartbeat_interval_ticks`	3	Leader heartbeat interval. Must be `< min`.
`tick_interval`	50ms	Wall-clock duration of one engine tick.

The engine is tick-driven. A tick is whatever you say it is.

Backpressure

Field	Default	Note
`max_pending_proposals`	1024	`propose` / `add_peer` / `remove_peer` return `Busy` above this in-flight count.
`max_pending_applies`	4096	Capacity of the driver → apply-task channel. When full, the driver awaits space.

Batching

Off by default. Turn it on if you have many concurrent proposals.

Field	Default	Note
`max_batch_delay_ticks`	0 (off)	Hold proposals for up to this many ticks before flushing.
`max_batch_entries`	64	Flush immediately when the buffer reaches this size.

With batching on, N concurrent propose calls can commit in a single broadcast and fsync.

Snapshotting

Field	Default	Note
`snapshot_hint_threshold_entries`	1024	The engine emits `Action::SnapshotHint` every time this many entries have been applied past the current floor. Set to `0` to disable.
`max_log_entries`	0 (off)	Live-log guardrail. When the number of log entries above the current snapshot floor exceeds this, the engine emits a `SnapshotHint` regardless of the applied-entries band. Protects against runaway log growth when apply is lagging.
`snapshot_chunk_size_bytes`	64 KiB	Maximum bytes per `InstallSnapshot` chunk.

Elections

Field	Default	Note
`pre_vote`	`true`	§9.6 pre-vote. A disrupted follower probes peers before bumping its term, so flapping nodes can’t force the rest of the cluster to step down on every reconnect.

Reads

Field	Default	Note
`lease_duration_ticks`	0 (off)	§9 leader-lease. When the leader has received a majority AE ack within this many ticks, linearizable reads skip the ReadIndex round-trip and return immediately. Must be strictly less than `election_timeout_min_ticks - heartbeat_interval_ticks`, otherwise `Config::validate` rejects it.

See rustdoc for Config for the full type.

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