diff options
Diffstat (limited to 'src/table/replication')
| -rw-r--r-- | src/table/replication/fullcopy.rs | 12 | ||||
| -rw-r--r-- | src/table/replication/mod.rs | 6 | ||||
| -rw-r--r-- | src/table/replication/parameters.rs | 10 | ||||
| -rw-r--r-- | src/table/replication/sharded.rs | 17 |
4 files changed, 28 insertions, 17 deletions
diff --git a/src/table/replication/fullcopy.rs b/src/table/replication/fullcopy.rs index bd658f63..a6b4c98c 100644 --- a/src/table/replication/fullcopy.rs +++ b/src/table/replication/fullcopy.rs @@ -6,19 +6,19 @@ use garage_util::data::*; use crate::replication::*; +/// Full replication schema: all nodes store everything +/// Writes are disseminated in an epidemic manner in the network +/// Advantage: do all reads locally, extremely fast +/// Inconvenient: only suitable to reasonably small tables #[derive(Clone)] pub struct TableFullReplication { + /// The membership manager of this node pub system: Arc<System>, + /// Max number of faults allowed while replicating a record pub max_faults: usize, } impl TableReplication for TableFullReplication { - // Full replication schema: all nodes store everything - // Writes are disseminated in an epidemic manner in the network - - // Advantage: do all reads locally, extremely fast - // Inconvenient: only suitable to reasonably small tables - fn read_nodes(&self, _hash: &Hash) -> Vec<UUID> { vec![self.system.id] } diff --git a/src/table/replication/mod.rs b/src/table/replication/mod.rs index d43d7f19..dfcb026a 100644 --- a/src/table/replication/mod.rs +++ b/src/table/replication/mod.rs @@ -1,6 +1,8 @@ mod parameters; -pub mod fullcopy; -pub mod sharded; +mod fullcopy; +mod sharded; +pub use fullcopy::TableFullReplication; pub use parameters::*; +pub use sharded::TableShardedReplication; diff --git a/src/table/replication/parameters.rs b/src/table/replication/parameters.rs index e46bd172..0ab9ee5a 100644 --- a/src/table/replication/parameters.rs +++ b/src/table/replication/parameters.rs @@ -2,20 +2,26 @@ use garage_rpc::ring::*; use garage_util::data::*; +/// Trait to describe how a table shall be replicated pub trait TableReplication: Send + Sync { // See examples in table_sharded.rs and table_fullcopy.rs // To understand various replication methods - // Which nodes to send reads from + /// Which nodes to send read requests to fn read_nodes(&self, hash: &Hash) -> Vec<UUID>; + /// Responses needed to consider a read succesfull fn read_quorum(&self) -> usize; - // Which nodes to send writes to + /// Which nodes to send writes to fn write_nodes(&self, hash: &Hash) -> Vec<UUID>; + /// Responses needed to consider a write succesfull fn write_quorum(&self) -> usize; + // this feels like its write_nodes().len() - write_quorum() fn max_write_errors(&self) -> usize; // Accessing partitions, for Merkle tree & sync + /// Get partition for data with given hash fn partition_of(&self, hash: &Hash) -> Partition; + /// List of existing partitions fn partitions(&self) -> Vec<(Partition, Hash)>; } diff --git a/src/table/replication/sharded.rs b/src/table/replication/sharded.rs index dce74b03..f2d89729 100644 --- a/src/table/replication/sharded.rs +++ b/src/table/replication/sharded.rs @@ -6,22 +6,25 @@ 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 { - // 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 - fn read_nodes(&self, hash: &Hash) -> Vec<UUID> { let ring = self.system.ring.borrow().clone(); ring.walk_ring(&hash, self.replication_factor) |