Struct openraft::MembershipState
source · pub struct MembershipState<NID, N>where
NID: NodeId,
N: Node,{ /* private fields */ }
Expand description
The state of membership configs a raft node needs to know.
A raft node needs to store at most 2 membership config log:
- The first(committed) one must have been committed, because (1): raft allows to propose new membership only when the previous one is committed.
- The second(effective) may be committed or not.
From (1) we have: (2) there is at most one outstanding, uncommitted membership log. On either leader or follower, the second last one must have been committed. A committed log must be consistent with the leader.
(3) By raft design, the last membership takes effect.
When handling append-entries RPC: (4) a raft follower will delete logs that are inconsistent with the leader.
From (3) and (4), a follower needs to revert the effective membership to the previous one.
From (2), a follower only need to revert at most one membership log.
Thus a raft node will only need to store at most two recent membership logs.
Implementations§
source§impl<NID, N> MembershipState<NID, N>where
NID: NodeId,
N: Node,
impl<NID, N> MembershipState<NID, N>where NID: NodeId, N: Node,
pub fn committed(&self) -> &Arc<EffectiveMembership<NID, N>>
pub fn effective(&self) -> &Arc<EffectiveMembership<NID, N>>
Trait Implementations§
source§impl<NID, N> Clone for MembershipState<NID, N>where
NID: NodeId + Clone,
N: Node + Clone,
impl<NID, N> Clone for MembershipState<NID, N>where NID: NodeId + Clone, N: Node + Clone,
source§fn clone(&self) -> MembershipState<NID, N>
fn clone(&self) -> MembershipState<NID, N>
Returns a copy of the value. Read more
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source
. Read moresource§impl<NID, N> Default for MembershipState<NID, N>where
NID: NodeId + Default,
N: Node + Default,
impl<NID, N> Default for MembershipState<NID, N>where NID: NodeId + Default, N: Node + Default,
source§fn default() -> MembershipState<NID, N>
fn default() -> MembershipState<NID, N>
Returns the “default value” for a type. Read more
source§impl<NID, N> MessageSummary<MembershipState<NID, N>> for MembershipState<NID, N>where
NID: NodeId,
N: Node,
impl<NID, N> MessageSummary<MembershipState<NID, N>> for MembershipState<NID, N>where NID: NodeId, N: Node,
source§impl<NID, N> PartialEq<MembershipState<NID, N>> for MembershipState<NID, N>where
NID: NodeId + PartialEq,
N: Node + PartialEq,
impl<NID, N> PartialEq<MembershipState<NID, N>> for MembershipState<NID, N>where NID: NodeId + PartialEq, N: Node + PartialEq,
source§fn eq(&self, other: &MembershipState<NID, N>) -> bool
fn eq(&self, other: &MembershipState<NID, N>) -> bool
This method tests for
self
and other
values to be equal, and is used
by ==
.impl<NID, N> Eq for MembershipState<NID, N>where NID: NodeId + Eq, N: Node + Eq,
impl<NID, N> StructuralEq for MembershipState<NID, N>where NID: NodeId, N: Node,
impl<NID, N> StructuralPartialEq for MembershipState<NID, N>where NID: NodeId, N: Node,
Auto Trait Implementations§
impl<NID, N> RefUnwindSafe for MembershipState<NID, N>where N: RefUnwindSafe, NID: RefUnwindSafe,
impl<NID, N> Send for MembershipState<NID, N>
impl<NID, N> Sync for MembershipState<NID, N>
impl<NID, N> Unpin for MembershipState<NID, N>
impl<NID, N> UnwindSafe for MembershipState<NID, N>where N: RefUnwindSafe, NID: RefUnwindSafe,
Blanket Implementations§
source§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
Compare self to
key
and return true
if they are equal.