use std::sync::Arc; use garage_rpc::ring::*; use garage_rpc::system::System; use garage_util::data::*; use crate::replication::*; /// Sharded replication schema: /// - based on the ring of nodes, a certain set of neighbors /// store entries, given as a function of the position of the /// entry's hash in the ring /// - reads are done on all of the nodes that replicate the data /// - writes as well #[derive(Clone)] pub struct TableShardedReplication { /// The membership manager of this node pub system: Arc<System>, /// How many time each data should be replicated pub replication_factor: usize, /// How many nodes to contact for a read, should be at most `replication_factor` pub read_quorum: usize, /// How many nodes to contact for a write, should be at most `replication_factor` pub write_quorum: usize, } impl TableReplication for TableShardedReplication { fn read_nodes(&self, hash: &Hash) -> Vec<Uuid> { let ring = self.system.ring.borrow(); ring.get_nodes(hash, self.replication_factor) } fn read_quorum(&self) -> usize { self.read_quorum } fn write_nodes(&self, hash: &Hash) -> Vec<Uuid> { let ring = self.system.ring.borrow(); ring.get_nodes(hash, self.replication_factor) } fn write_quorum(&self) -> usize { self.write_quorum } fn max_write_errors(&self) -> usize { self.replication_factor - self.write_quorum } fn partition_of(&self, hash: &Hash) -> Partition { self.system.ring.borrow().partition_of(hash) } fn partitions(&self) -> Vec<(Partition, Hash)> { self.system.ring.borrow().partitions() } }