Struct ChaosConfiguration 

pub struct ChaosConfiguration {

    pub clog_probability: f64,
    pub clog_duration: Range<Duration>,
    pub partition_probability: f64,
    pub partition_duration: Range<Duration>,
    pub bit_flip_probability: f64,
    pub bit_flip_min_bits: u32,
    pub bit_flip_max_bits: u32,
    pub bit_flip_cooldown: Duration,
    pub partial_write_max_bytes: usize,
    pub partial_read_max_bytes: usize,
    pub random_close_probability: f64,
    pub random_close_cooldown: Duration,
    pub random_close_explicit_ratio: f64,
    pub clock_drift_enabled: bool,
    pub clock_drift_max: Duration,
    pub buggified_delay_enabled: bool,
    pub buggified_delay_max: Duration,
    pub buggified_delay_probability: f64,
    pub connect_failure_mode: ConnectFailureMode,
    pub connect_failure_probability: f64,
    pub max_pair_latency: Range<Duration>,
    pub partition_strategy: PartitionStrategy,
}

Configuration for chaos injection in simulations.

This struct contains all settings related to fault injection and chaos testing, following FoundationDB’s BUGGIFY patterns for deterministic testing.

Fields

clog_probability: f64

Clogging probability for individual writes (0.0 - 1.0)

clog_duration: Range<Duration>

Duration range for clog delays

partition_probability: f64

Network partition probability (0.0 - 1.0)

partition_duration: Range<Duration>

Duration range for network partitions

bit_flip_probability: f64

Bit flip probability for packet corruption (0.0 - 1.0)

bit_flip_min_bits: u32

Minimum number of bits to flip (power-law distribution lower bound)

bit_flip_max_bits: u32

Maximum number of bits to flip (power-law distribution upper bound)

bit_flip_cooldown: Duration

Cooldown duration after bit flip to prevent excessive corruption

partial_write_max_bytes: usize

Maximum bytes for partial write simulation (BUGGIFY truncates writes to 0-max_bytes) Following FDB’s approach of truncating writes to test TCP backpressure handling

partial_read_max_bytes: usize

Maximum bytes for partial read simulation (BUGGIFY truncates reads to 1-max_bytes) Mirrors FDB’s Sim2Conn partial delivery on the receiver to test short reads and message reassembly. Always delivers at least one byte so a partial read is never mistaken for EOF.

random_close_probability: f64

Random connection close probability per I/O operation (0.0 - 1.0) FDB default: 0.00001 (0.001%) - see sim2.actor.cpp:584

random_close_cooldown: Duration

Cooldown duration after a random close event (prevents cascading failures) FDB uses connectionFailuresDisableDuration - see sim2.actor.cpp:583

random_close_explicit_ratio: f64

Ratio of explicit exceptions vs silent failures (0.0 - 1.0) FDB default: 0.3 (30% explicit) - see sim2.actor.cpp:602

clock_drift_enabled: bool

Enable clock drift simulation When enabled, timer() can return a time up to clock_drift_max ahead of now() FDB ref: sim2.actor.cpp:1058-1064

clock_drift_max: Duration

Maximum clock drift (default 100ms per FDB) timer() can be up to this much ahead of now()

buggified_delay_enabled: bool

Enable buggified delays on sleep/timer operations When enabled, 25% of sleep operations get extra delay FDB ref: sim2.actor.cpp:1100-1105

buggified_delay_max: Duration

Maximum additional delay for buggified sleep (default 100ms) Uses power-law distribution: max_delay * pow(random01(), 1000.0) FDB ref: sim2.actor.cpp:1104

buggified_delay_probability: f64

Probability of adding buggified delay (default 25% per FDB)

connect_failure_mode: ConnectFailureMode

Connection establishment failure mode (per FDB) FDB ref: sim2.actor.cpp:1243-1250 (SIM_CONNECT_ERROR_MODE)

connect_failure_probability: f64

Probability of connect failure when Probabilistic mode is enabled (default 50%)

max_pair_latency: Range<Duration>

Permanent per-IP-pair latency range (FDB SimClogging::MAX_CLOGGING_LATENCY). Each ordered IP pair samples a fixed latency from this range at first contact (via sample_duration), then adds it to every delivery on that pair for the whole run — modelling a stably-slow link. An all-zero range (end is zero) disables it, leaving behavior unchanged. FDB’s MAX * random01() is the ZERO..MAX case. FDB ref: sim2.actor.cpp ~294-299, 352-354.

partition_strategy: PartitionStrategy

Network partition strategy. Controls how nodes are selected for partitioning. TigerBeetle ref: packet_simulator.zig partition modes

Real-World Scenario

Different strategies test different failure scenarios:

• Random: unpredictable chaos
• UniformSize: various quorum sizes
• IsolateSingle: single node isolation (common in production)

Implementations

impl ChaosConfiguration

pub fn disabled() -> Self

Create a configuration with all chaos disabled (for fast local testing)

pub fn random_for_seed() -> Self

Create a randomized chaos configuration for seed-based testing

pub fn swarm_for_seed() -> Self

Create a swarm-testing chaos configuration for seed-based testing.

Starts from random_for_seed, then disables each fault family with ~50% probability (drawn from the independent CONFIG_RNG stream). This implements swarm testing (Groce et al., ISSTA 2012): each seed exercises a random subset of fault families — including the all-off subset — instead of every family being slightly on at once (which lets families crowd each other out, the passive-suppression anti-pattern).

pub fn apply_buggify_knobs(&mut self)

Spike selected fault magnitudes under buggify (FDB’s if (randomize && BUGGIFY) KNOB = random(lo, hi)).

Composes on top of random_for_seed / swarm_for_seed: each knob keeps its sampled value unless its own buggify_knob! call site fires for the seed, in which case it jumps to an aggressive value within bounds. A representative subset — extend by adding more buggify_knob! lines.

Trait Implementations

impl Clone for ChaosConfiguration

fn clone(&self) -> ChaosConfiguration

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ChaosConfiguration

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

Formats the value using the given formatter.

impl Default for ChaosConfiguration

fn default() -> Self

Returns the “default value” for a type.