Struct MemberlistOptions

pub struct MemberlistOptions {

    pub timeout: Duration,
    pub indirect_checks: usize,
    pub retransmit_mult: usize,
    pub suspicion_mult: usize,
    pub suspicion_max_timeout_mult: usize,
    pub push_pull_interval: Duration,
    pub probe_interval: Duration,
    pub probe_timeout: Duration,
    pub disable_promised_pings: bool,
    pub awareness_max_multiplier: usize,
    pub gossip_interval: Duration,
    pub gossip_nodes: usize,
    pub gossip_to_the_dead_time: Duration,
    pub protocol_version: ProtocolVersion,
    pub delegate_version: DelegateVersion,
    pub handoff_queue_depth: usize,
    pub dead_node_reclaim_time: Duration,
    pub queue_check_interval: Duration,
    pub metric_labels: Arc<MetricLabels>,
}

Options used to configure the memberlist.

Fields

timeout: Duration

The timeout for establishing a stream connection with a remote node for a full state sync, and for stream read and write operations.

indirect_checks: usize

The number of nodes that will be asked to perform an indirect probe of a node in the case a direct probe fails. Memberlist waits for an ack from any single indirect node, so increasing this number will increase the likelihood that an indirect probe will succeed at the expense of bandwidth.

retransmit_mult: usize

The multiplier for the number of retransmissions that are attempted for messages broadcasted over gossip. The actual count of retransmissions is calculated using the formula:

retransmits = retransmit_mult * log(N+1)

This allows the retransmits to scale properly with cluster size. The higher the multiplier, the more likely a failed broadcast is to converge at the expense of increased bandwidth.

suspicion_mult: usize

The multiplier for determining the time an inaccessible node is considered suspect before declaring it dead. The actual timeout is calculated using the formula:

suspicion_timeout = suspicion_mult * log(N+1) * probe_interval

This allows the timeout to scale properly with expected propagation delay with a larger cluster size. The higher the multiplier, the longer an inaccessible node is considered part of the cluster before declaring it dead, giving that suspect node more time to refute if it is indeed still alive.

suspicion_max_timeout_mult: usize

The multiplier applied to the suspicion_timeout used as an upper bound on detection time. This max timeout is calculated using the formula:

suspicion_max_timeout = suspicion_max_timeout_mult * suspicion_timeout

If everything is working properly, confirmations from other nodes will accelerate suspicion timers in a manner which will cause the timeout to reach the base SuspicionTimeout before that elapses, so this value will typically only come into play if a node is experiencing issues communicating with other nodes. It should be set to a something fairly large so that a node having problems will have a lot of chances to recover before falsely declaring other nodes as failed, but short enough for a legitimately isolated node to still make progress marking nodes failed in a reasonable amount of time.

push_pull_interval: Duration

The interval between complete state syncs. Complete state syncs are done with a single node over TCP and are quite expensive relative to standard gossiped messages. Setting this to zero will disable state push/pull syncs completely.

Setting this interval lower (more frequent) will increase convergence speeds across larger clusters at the expense of increased bandwidth usage.

probe_interval: Duration

The interval between random node probes. Setting this lower (more frequent) will cause the memberlist cluster to detect failed nodes more quickly at the expense of increased bandwidth usage

probe_timeout: Duration

The timeout to wait for an ack from a probed node before assuming it is unhealthy. This should be set to 99-percentile of RTT (round-trip time) on your network.

disable_promised_pings: bool

Set this field will turn off the fallback promised pings that are attempted if the direct unreliable ping fails. These get pipelined along with the indirect unreliable pings.

awareness_max_multiplier: usize

Increase the probe interval if the node becomes aware that it might be degraded and not meeting the soft real time requirements to reliably probe other nodes.

gossip_interval: Duration

The interval between sending messages that need to be gossiped that haven’t been able to piggyback on probing messages. If this is set to zero, non-piggyback gossip is disabled. By lowering this value (more frequent) gossip messages are propagated across the cluster more quickly at the expense of increased bandwidth.

gossip_nodes: usize

The number of random nodes to send gossip messages to per gossip_interval. Increasing this number causes the gossip messages to propagate across the cluster more quickly at the expense of increased bandwidth.

gossip_to_the_dead_time: Duration

The interval after which a node has died that we will still try to gossip to it. This gives it a chance to refute.

protocol_version: ProtocolVersion

Used to guarantee protocol-compatibility

delegate_version: DelegateVersion

Used to guarantee protocol-compatibility for any custom messages that the delegate might do (broadcasts, local/remote state, etc.). If you don’t set these, then the protocol versions will just be zero, and version compliance won’t be done.

handoff_queue_depth: usize

Size of Memberlist’s internal channel which handles UDP messages. The size of this determines the size of the queue which Memberlist will keep while UDP messages are handled.

dead_node_reclaim_time: Duration

Controls the time before a dead node’s name can be reclaimed by one with a different address or port. By default, this is 0, meaning nodes cannot be reclaimed this way.

queue_check_interval: Duration

The interval at which we check the message queue to apply the warning and max depth.

metric_labels: Arc<MetricLabels>

The metric labels for the memberlist.

Implementations

impl Options

pub const fn timeout(&self) -> Duration

Returns the timeout for establishing a stream connection with a remote node for a full state sync, and for stream read and write operations.

pub const fn indirect_checks(&self) -> usize

Returns the number of nodes that will be asked to perform an indirect probe of a node in the case a direct probe fails.

pub const fn retransmit_mult(&self) -> usize

Returns the retransmit mult

pub const fn suspicion_mult(&self) -> usize

Returns the suspicion mult

pub const fn suspicion_max_timeout_mult(&self) -> usize

Returns the suspicion max timeout mult

pub const fn push_pull_interval(&self) -> Duration

Returns the push pull interval

pub const fn probe_interval(&self) -> Duration

Returns the probe interval

pub const fn probe_timeout(&self) -> Duration

Returns the probe timeout

pub const fn disable_promised_pings(&self) -> bool

Returns whether disable promised pings or not

pub const fn awareness_max_multiplier(&self) -> usize

Returns the awareness max multiplier

pub const fn gossip_interval(&self) -> Duration

Returns the gossip interval

pub const fn gossip_nodes(&self) -> usize

Returns the gossip nodes

pub const fn gossip_to_the_dead_time(&self) -> Duration

Returns the gossip to the dead timeout

pub const fn protocol_version(&self) -> ProtocolVersion

Returns the protocol version this node is speaking

pub const fn delegate_version(&self) -> DelegateVersion

Returns the delegate version this node is speaking

pub const fn handoff_queue_depth(&self) -> usize

Returns the handoff queue depth

pub const fn dead_node_reclaim_time(&self) -> Duration

Returns the dead node reclaim time

pub const fn queue_check_interval(&self) -> Duration

Returns the queue check interval

pub const fn metric_labels(&self) -> &Arc<MetricLabels>

Get the metric labels for the memberlist.

pub const fn with_timeout(self, val: Duration) -> Options

Sets the timeout for establishing a stream connection with a remote node for a full state sync, and for stream read and write operations (Builder pattern).

pub const fn with_indirect_checks(self, val: usize) -> Options

Sets the number of nodes that will be asked to perform an indirect probe of a node in the case a direct probe fails (Builder pattern).

pub const fn with_retransmit_mult(self, val: usize) -> Options

Sets the retransmit mult (Builder pattern).

pub const fn with_suspicion_mult(self, val: usize) -> Options

Sets the suspicion mult (Builder pattern).

pub const fn with_suspicion_max_timeout_mult(self, val: usize) -> Options

Sets the suspicion max timeout mult (Builder pattern).

pub const fn with_push_pull_interval(self, val: Duration) -> Options

Sets the push pull interval (Builder pattern).

pub const fn with_probe_interval(self, val: Duration) -> Options

Sets the probe interval (Builder pattern).

pub const fn with_probe_timeout(self, val: Duration) -> Options

Sets the probe timeout (Builder pattern).

pub const fn with_disable_promised_pings(self, val: bool) -> Options

Sets whether disable promised pings or not (Builder pattern).

pub const fn with_awareness_max_multiplier(self, val: usize) -> Options

Sets the awareness max multiplier (Builder pattern).

pub const fn with_gossip_interval(self, val: Duration) -> Options

Sets the gossip interval (Builder pattern).

pub const fn with_gossip_nodes(self, val: usize) -> Options

Sets the gossip nodes (Builder pattern).

pub const fn with_gossip_to_the_dead_time(self, val: Duration) -> Options

Sets the gossip to the dead timeout (Builder pattern).

pub const fn with_protocol_version(self, val: ProtocolVersion) -> Options

Sets the protocol version this node is speaking (Builder pattern).

pub const fn with_delegate_version(self, val: DelegateVersion) -> Options

Sets the delegate version this node is speaking (Builder pattern).

pub const fn with_handoff_queue_depth(self, val: usize) -> Options

Sets the handoff queue depth (Builder pattern).

pub const fn with_dead_node_reclaim_time(self, val: Duration) -> Options

Sets the dead node reclaim time (Builder pattern).

pub const fn with_queue_check_interval(self, val: Duration) -> Options

Sets the queue check interval (Builder pattern).

pub fn with_metric_labels(self, val: Arc<MetricLabels>) -> Options

Sets the metric labels for the memberlist.

impl Options

pub fn lan() -> Options

Returns a sane set of configurations for Memberlist. Sets very conservative values that are sane for most LAN environments. The default configuration errs on the side of caution, choosing values that are optimized for higher convergence at the cost of higher bandwidth usage. Regardless, these values are a good starting point when getting started with memberlist.

pub fn wan() -> Options

Returns a configuration that is optimized for most WAN environments. The default configuration is still very conservative and errs on the side of caution.

pub fn local() -> Options

Returns a configuration that is optimized for a local loopback environments. The default configuration is still very conservative and errs on the side of caution.

Trait Implementations

impl Clone for Options

fn clone(&self) -> Options

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Options

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

Formats the value using the given formatter.

impl Default for Options

fn default() -> Options

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Options

fn deserialize<__D>( __deserializer: __D, ) -> Result<Options, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Options

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

where __S: Serializer,

Serialize this value into the given Serde serializer.