forked from Deuxfleurs/garage
Mendes
ceac3713d6
- have consistent error return types - store the zone redundancy in a Lww - print the error and message in the CLI (TODO: for the server Api, should msg be returned in the body response?)
961 lines
35 KiB
Rust
961 lines
35 KiB
Rust
use std::cmp::Ordering;
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use std::collections::HashMap;
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use std::collections::HashSet;
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use hex::ToHex;
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use itertools::Itertools;
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use serde::{Deserialize, Serialize};
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use garage_util::crdt::{AutoCrdt, Crdt, LwwMap, Lww};
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use garage_util::data::*;
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use garage_util::error::*;
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use crate::graph_algo::*;
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use crate::ring::*;
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use std::convert::TryInto;
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//The Message type will be used to collect information on the algorithm.
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type Message = Vec<String>;
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/// The layout of the cluster, i.e. the list of roles
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/// which are assigned to each cluster node
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#[derive(Clone, Debug, Serialize, Deserialize)]
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pub struct ClusterLayout {
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pub version: u64,
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pub replication_factor: usize,
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//This attribute is only used to retain the previously computed partition size,
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//to know to what extent does it change with the layout update.
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#[serde(default="default_partition_size")]
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pub partition_size: u32,
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pub roles: LwwMap<Uuid, NodeRoleV>,
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/// node_id_vec: a vector of node IDs with a role assigned
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/// in the system (this includes gateway nodes).
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/// The order here is different than the vec stored by `roles`, because:
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/// 1. non-gateway nodes are first so that they have lower numbers holding
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/// in u8 (the number of non-gateway nodes is at most 256).
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/// 2. nodes that don't have a role are excluded (but they need to
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/// stay in the CRDT as tombstones)
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pub node_id_vec: Vec<Uuid>,
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/// the assignation of data partitions to node, the values
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/// are indices in node_id_vec
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#[serde(with = "serde_bytes")]
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pub ring_assignation_data: Vec<CompactNodeType>,
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/// Role changes which are staged for the next version of the layout
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#[serde(default="default_layout_parameters")]
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pub parameters: Lww<LayoutParameters>,
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pub staging: LwwMap<Uuid, NodeRoleV>,
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pub staging_hash: Hash,
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}
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fn default_partition_size() -> u32{
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return 0;
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}
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fn default_layout_parameters() -> Lww<LayoutParameters>{
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Lww::<LayoutParameters>::new(LayoutParameters{ zone_redundancy: 1})
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}
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///This struct is used to set the parameters to be used in the assignation computation
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///algorithm. It is stored as a Crdt.
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#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
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pub struct LayoutParameters {
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pub zone_redundancy:usize,
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}
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impl AutoCrdt for LayoutParameters {
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const WARN_IF_DIFFERENT: bool = true;
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}
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const NB_PARTITIONS : usize = 1usize << PARTITION_BITS;
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#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
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pub struct NodeRoleV(pub Option<NodeRole>);
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impl AutoCrdt for NodeRoleV {
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const WARN_IF_DIFFERENT: bool = true;
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}
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/// The user-assigned roles of cluster nodes
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#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
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pub struct NodeRole {
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/// Datacenter at which this entry belong. This information might be used to perform a better
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/// geodistribution
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pub zone: String,
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/// The (relative) capacity of the node
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/// If this is set to None, the node does not participate in storing data for the system
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/// and is only active as an API gateway to other nodes
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pub capacity: Option<u32>,
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/// A set of tags to recognize the node
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pub tags: Vec<String>,
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}
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impl NodeRole {
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pub fn capacity_string(&self) -> String {
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match self.capacity {
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Some(c) => format!("{}", c),
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None => "gateway".to_string(),
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}
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}
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pub fn tags_string(&self) -> String {
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let mut tags = String::new();
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if self.tags.len() == 0 {
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return tags
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}
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tags.push_str(&self.tags[0].clone());
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for t in 1..self.tags.len(){
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tags.push_str(",");
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tags.push_str(&self.tags[t].clone());
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}
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return tags;
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}
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}
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impl ClusterLayout {
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pub fn new(replication_factor: usize) -> Self {
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//We set the default zone redundancy to be equal to the replication factor,
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//i.e. as strict as possible.
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let default_parameters = Lww::<LayoutParameters>::new(
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LayoutParameters{ zone_redundancy: replication_factor});
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let empty_lwwmap = LwwMap::new();
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let empty_lwwmap_hash = blake2sum(&rmp_to_vec_all_named(&empty_lwwmap).unwrap()[..]);
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ClusterLayout {
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version: 0,
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replication_factor,
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partition_size: 0,
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roles: LwwMap::new(),
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node_id_vec: Vec::new(),
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ring_assignation_data: Vec::new(),
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parameters: default_parameters,
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staging: empty_lwwmap,
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staging_hash: empty_lwwmap_hash,
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}
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}
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pub fn merge(&mut self, other: &ClusterLayout) -> bool {
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match other.version.cmp(&self.version) {
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Ordering::Greater => {
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*self = other.clone();
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true
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}
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Ordering::Equal => {
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self.parameters.merge(&other.parameters);
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self.staging.merge(&other.staging);
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let new_staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
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let changed = new_staging_hash != self.staging_hash;
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self.staging_hash = new_staging_hash;
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changed
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}
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Ordering::Less => false,
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}
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}
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pub fn apply_staged_changes(mut self, version: Option<u64>) -> Result<(Self,Message), Error> {
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match version {
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None => {
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let error = r#"
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Please pass the new layout version number to ensure that you are writing the correct version of the cluster layout.
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To know the correct value of the new layout version, invoke `garage layout show` and review the proposed changes.
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"#;
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return Err(Error::Message(error.into()));
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}
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Some(v) => {
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if v != self.version + 1 {
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return Err(Error::Message("Invalid new layout version".into()));
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}
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}
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}
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self.roles.merge(&self.staging);
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self.roles.retain(|(_, _, v)| v.0.is_some());
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let msg = self.calculate_partition_assignation()?;
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self.staging.clear();
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self.staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
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self.version += 1;
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Ok((self,msg))
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}
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pub fn revert_staged_changes(mut self, version: Option<u64>) -> Result<Self, Error> {
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match version {
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None => {
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let error = r#"
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Please pass the new layout version number to ensure that you are writing the correct version of the cluster layout.
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To know the correct value of the new layout version, invoke `garage layout show` and review the proposed changes.
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"#;
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return Err(Error::Message(error.into()));
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}
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Some(v) => {
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if v != self.version + 1 {
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return Err(Error::Message("Invalid new layout version".into()));
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}
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}
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}
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self.staging.clear();
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self.staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
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self.version += 1;
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Ok(self)
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}
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/// Returns a list of IDs of nodes that currently have
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/// a role in the cluster
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pub fn node_ids(&self) -> &[Uuid] {
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&self.node_id_vec[..]
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}
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pub fn num_nodes(&self) -> usize {
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self.node_id_vec.len()
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}
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/// Returns the role of a node in the layout
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pub fn node_role(&self, node: &Uuid) -> Option<&NodeRole> {
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match self.roles.get(node) {
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Some(NodeRoleV(Some(v))) => Some(v),
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_ => None,
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}
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}
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///Returns the uuids of the non_gateway nodes in self.node_id_vec.
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pub fn useful_nodes(&self) -> Vec<Uuid> {
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let mut result = Vec::<Uuid>::new();
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for uuid in self.node_id_vec.iter() {
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match self.node_role(uuid) {
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Some(role) if role.capacity != None => result.push(*uuid),
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_ => ()
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}
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}
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return result;
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}
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///Given a node uuids, this function returns the label of its zone
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pub fn get_node_zone(&self, uuid : &Uuid) -> Result<String,Error> {
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match self.node_role(uuid) {
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Some(role) => return Ok(role.zone.clone()),
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_ => return Err(Error::Message("The Uuid does not correspond to a node present in the cluster.".into()))
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}
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}
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///Given a node uuids, this function returns its capacity or fails if it does not have any
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pub fn get_node_capacity(&self, uuid : &Uuid) -> Result<u32,Error> {
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match self.node_role(uuid) {
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Some(NodeRole{capacity : Some(cap), zone: _, tags: _}) => return Ok(*cap),
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_ => return Err(Error::Message("The Uuid does not correspond to a node present in the \
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cluster or this node does not have a positive capacity.".into()))
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}
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}
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///Returns the sum of capacities of non gateway nodes in the cluster
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pub fn get_total_capacity(&self) -> Result<u32,Error> {
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let mut total_capacity = 0;
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for uuid in self.useful_nodes().iter() {
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total_capacity += self.get_node_capacity(uuid)?;
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}
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return Ok(total_capacity);
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}
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/// Check a cluster layout for internal consistency
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/// returns true if consistent, false if error
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pub fn check(&self) -> bool {
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// Check that the hash of the staging data is correct
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let staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
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if staging_hash != self.staging_hash {
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return false;
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}
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// Check that node_id_vec contains the correct list of nodes
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let mut expected_nodes = self
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.roles
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.items()
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.iter()
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.filter(|(_, _, v)| v.0.is_some())
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.map(|(id, _, _)| *id)
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.collect::<Vec<_>>();
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expected_nodes.sort();
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let mut node_id_vec = self.node_id_vec.clone();
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node_id_vec.sort();
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if expected_nodes != node_id_vec {
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return false;
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}
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// Check that the assignation data has the correct length
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if self.ring_assignation_data.len() != (1 << PARTITION_BITS) * self.replication_factor {
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return false;
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}
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// Check that the assigned nodes are correct identifiers
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// of nodes that are assigned a role
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// and that role is not the role of a gateway nodes
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for x in self.ring_assignation_data.iter() {
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if *x as usize >= self.node_id_vec.len() {
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return false;
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}
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let node = self.node_id_vec[*x as usize];
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match self.roles.get(&node) {
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Some(NodeRoleV(Some(x))) if x.capacity.is_some() => (),
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_ => return false,
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}
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}
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//Check that every partition is associated to distinct nodes
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let rf = self.replication_factor;
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for p in 0..(1 << PARTITION_BITS) {
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let nodes_of_p = self.ring_assignation_data[rf*p..rf*(p+1)].to_vec();
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if nodes_of_p.iter().unique().count() != rf {
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return false;
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}
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//Check that every partition is spread over at least zone_redundancy zones.
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let zones_of_p = nodes_of_p.iter()
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.map(|n| self.get_node_zone(&self.node_id_vec[*n as usize])
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.expect("Zone not found."));
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let redundancy = self.parameters.get().zone_redundancy;
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if zones_of_p.unique().count() < redundancy {
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return false;
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}
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}
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//Check that the nodes capacities is consistent with the stored partitions
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let mut node_usage = vec![0; MAX_NODE_NUMBER];
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for n in self.ring_assignation_data.iter() {
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node_usage[*n as usize] += 1;
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}
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for n in 0..MAX_NODE_NUMBER {
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if node_usage[n] > 0 {
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let uuid = self.node_id_vec[n];
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if node_usage[n]*self.partition_size > self.get_node_capacity(&uuid)
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.expect("Critical Error"){
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return false;
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}
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}
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}
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//Check that the partition size stored is the one computed by the asignation
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//algorithm.
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let cl2 = self.clone();
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let (_ , zone_to_id) = cl2.generate_zone_ids().expect("Critical Error");
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let partition_size = cl2.compute_optimal_partition_size(&zone_to_id).expect("Critical Error");
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if partition_size != self.partition_size {
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return false;
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}
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true
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}
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}
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impl ClusterLayout {
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/// This function calculates a new partition-to-node assignation.
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/// The computed assignation respects the node replication factor
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/// and the zone redundancy parameter It maximizes the capacity of a
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/// partition (assuming all partitions have the same size).
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/// Among such optimal assignation, it minimizes the distance to
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/// the former assignation (if any) to minimize the amount of
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/// data to be moved.
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pub fn calculate_partition_assignation(&mut self) -> Result<Message,Error> {
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//The nodes might have been updated, some might have been deleted.
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//So we need to first update the list of nodes and retrieve the
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//assignation.
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//We update the node ids, since the node list might have changed with the staged
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//changes in the layout. We retrieve the old_assignation reframed with the new ids
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let old_assignation_opt = self.update_node_id_vec()?;
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let redundancy = self.parameters.get().zone_redundancy;
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let mut msg = Message::new();
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msg.push(format!("Computation of a new cluster layout where partitions are \
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replicated {} times on at least {} distinct zones.", self.replication_factor, redundancy));
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//We generate for once numerical ids for the zone, to use them as indices in the
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//flow graphs.
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let (id_to_zone , zone_to_id) = self.generate_zone_ids()?;
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msg.push(format!("The cluster contains {} nodes spread over {} zones.",
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self.useful_nodes().len(), id_to_zone.len()));
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//We compute the optimal partition size
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//Capacities should be given in a unit so that partition size is at least 100.
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//In this case, integer rounding plays a marginal role in the percentages of
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//optimality.
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let partition_size = self.compute_optimal_partition_size(&zone_to_id)?;
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if old_assignation_opt != None {
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msg.push(format!("Given the replication and redundancy constraint, the \
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optimal size of a partition is {}. In the previous layout, it used to \
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be {}.", partition_size, self.partition_size));
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}
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else {
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msg.push(format!("Given the replication and redundancy constraints, the \
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optimal size of a partition is {}.", partition_size));
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}
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self.partition_size = partition_size;
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if partition_size < 100 {
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msg.push("WARNING: The partition size is low (< 100), you might consider to \
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give the nodes capacities in a smaller unit (e.g. Mb instead of Gb) to \
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achieve a more tailored use of your storage ressources.".into());
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}
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//We compute a first flow/assignment that is heuristically close to the previous
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//assignment
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let mut gflow = self.compute_candidate_assignment( &zone_to_id, &old_assignation_opt)?;
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if let Some(assoc) = &old_assignation_opt {
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//We minimize the distance to the previous assignment.
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self.minimize_rebalance_load(&mut gflow, &zone_to_id, &assoc)?;
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}
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msg.append(&mut self.output_stat(&gflow, &old_assignation_opt, &zone_to_id,&id_to_zone)?);
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msg.push("".to_string());
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//We update the layout structure
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self.update_ring_from_flow(id_to_zone.len() , &gflow)?;
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return Ok(msg);
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}
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/// The LwwMap of node roles might have changed. This function updates the node_id_vec
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/// and returns the assignation given by ring, with the new indices of the nodes, and
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/// None if the node is not present anymore.
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/// We work with the assumption that only this function and calculate_new_assignation
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/// do modify assignation_ring and node_id_vec.
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fn update_node_id_vec(&mut self) -> Result< Option< Vec<Vec<usize> > > ,Error> {
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// (1) We compute the new node list
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//Non gateway nodes should be coded on 8bits, hence they must be first in the list
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//We build the new node ids
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let mut new_non_gateway_nodes: Vec<Uuid> = self.roles.items().iter()
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.filter(|(_, _, v)|
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match &v.0 {Some(r) if r.capacity != None => true, _=> false })
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.map(|(k, _, _)| *k).collect();
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if new_non_gateway_nodes.len() > MAX_NODE_NUMBER {
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return Err(Error::Message(format!("There are more than {} non-gateway nodes in the new \
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layout. This is not allowed.", MAX_NODE_NUMBER).into() ));
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}
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let mut new_gateway_nodes: Vec<Uuid> = self.roles.items().iter()
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.filter(|(_, _, v)|
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match v {NodeRoleV(Some(r)) if r.capacity == None => true, _=> false })
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.map(|(k, _, _)| *k).collect();
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let nb_useful_nodes = new_non_gateway_nodes.len();
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let mut new_node_id_vec = Vec::<Uuid>::new();
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new_node_id_vec.append(&mut new_non_gateway_nodes);
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new_node_id_vec.append(&mut new_gateway_nodes);
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// (2) We retrieve the old association
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//We rewrite the old association with the new indices. We only consider partition
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//to node assignations where the node is still in use.
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let nb_partitions = 1usize << PARTITION_BITS;
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let mut old_assignation = vec![ Vec::<usize>::new() ; nb_partitions];
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if self.ring_assignation_data.len() == 0 {
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//This is a new association
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return Ok(None);
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}
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if self.ring_assignation_data.len() != nb_partitions * self.replication_factor {
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return Err(Error::Message("The old assignation does not have a size corresponding to \
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the old replication factor or the number of partitions.".into()));
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}
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//We build a translation table between the uuid and new ids
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let mut uuid_to_new_id = HashMap::<Uuid, usize>::new();
|
|
|
|
//We add the indices of only the new non-gateway nodes that can be used in the
|
|
//association ring
|
|
for i in 0..nb_useful_nodes {
|
|
uuid_to_new_id.insert(new_node_id_vec[i], i );
|
|
}
|
|
|
|
let rf= self.replication_factor;
|
|
for p in 0..nb_partitions {
|
|
for old_id in &self.ring_assignation_data[p*rf..(p+1)*rf] {
|
|
let uuid = self.node_id_vec[*old_id as usize];
|
|
if uuid_to_new_id.contains_key(&uuid) {
|
|
old_assignation[p].push(uuid_to_new_id[&uuid]);
|
|
}
|
|
}
|
|
}
|
|
|
|
//We write the results
|
|
self.node_id_vec = new_node_id_vec;
|
|
self.ring_assignation_data = Vec::<CompactNodeType>::new();
|
|
|
|
return Ok(Some(old_assignation));
|
|
}
|
|
|
|
|
|
///This function generates ids for the zone of the nodes appearing in
|
|
///self.node_id_vec.
|
|
fn generate_zone_ids(&self) -> Result<(Vec<String>, HashMap<String, usize>),Error>{
|
|
let mut id_to_zone = Vec::<String>::new();
|
|
let mut zone_to_id = HashMap::<String,usize>::new();
|
|
|
|
for uuid in self.node_id_vec.iter() {
|
|
if self.roles.get(uuid) == None {
|
|
return Err(Error::Message("The uuid was not found in the node roles (this should \
|
|
not happen, it might be a critical error).".into()));
|
|
}
|
|
match self.node_role(&uuid) {
|
|
Some(r) => if !zone_to_id.contains_key(&r.zone) && r.capacity != None {
|
|
zone_to_id.insert(r.zone.clone() , id_to_zone.len());
|
|
id_to_zone.push(r.zone.clone());
|
|
}
|
|
_ => ()
|
|
}
|
|
}
|
|
return Ok((id_to_zone, zone_to_id));
|
|
}
|
|
|
|
///This function computes by dichotomy the largest realizable partition size, given
|
|
///the layout.
|
|
fn compute_optimal_partition_size(&self, zone_to_id: &HashMap<String, usize>) -> Result<u32,Error>{
|
|
let nb_partitions = 1usize << PARTITION_BITS;
|
|
let empty_set = HashSet::<(usize,usize)>::new();
|
|
let mut g = self.generate_flow_graph(1, zone_to_id, &empty_set)?;
|
|
g.compute_maximal_flow()?;
|
|
if g.get_flow_value()? < (nb_partitions*self.replication_factor).try_into().unwrap() {
|
|
return Err(Error::Message("The storage capacity of he cluster is to small. It is \
|
|
impossible to store partitions of size 1.".into()));
|
|
}
|
|
|
|
let mut s_down = 1;
|
|
let mut s_up = self.get_total_capacity()?;
|
|
while s_down +1 < s_up {
|
|
g = self.generate_flow_graph((s_down+s_up)/2, zone_to_id, &empty_set)?;
|
|
g.compute_maximal_flow()?;
|
|
if g.get_flow_value()? < (nb_partitions*self.replication_factor).try_into().unwrap() {
|
|
s_up = (s_down+s_up)/2;
|
|
}
|
|
else {
|
|
s_down = (s_down+s_up)/2;
|
|
}
|
|
}
|
|
|
|
return Ok(s_down);
|
|
}
|
|
|
|
fn generate_graph_vertices(nb_zones : usize, nb_nodes : usize) -> Vec<Vertex> {
|
|
let mut vertices = vec![Vertex::Source, Vertex::Sink];
|
|
for p in 0..NB_PARTITIONS {
|
|
vertices.push(Vertex::Pup(p));
|
|
vertices.push(Vertex::Pdown(p));
|
|
for z in 0..nb_zones {
|
|
vertices.push(Vertex::PZ(p, z));
|
|
}
|
|
}
|
|
for n in 0..nb_nodes {
|
|
vertices.push(Vertex::N(n));
|
|
}
|
|
return vertices;
|
|
}
|
|
|
|
fn generate_flow_graph(&self, size: u32, zone_to_id: &HashMap<String, usize>, exclude_assoc : &HashSet<(usize,usize)>) -> Result<Graph<FlowEdge>, Error> {
|
|
let vertices = ClusterLayout::generate_graph_vertices(zone_to_id.len(),
|
|
self.useful_nodes().len());
|
|
let mut g= Graph::<FlowEdge>::new(&vertices);
|
|
let nb_zones = zone_to_id.len();
|
|
let redundancy = self.parameters.get().zone_redundancy;
|
|
for p in 0..NB_PARTITIONS {
|
|
g.add_edge(Vertex::Source, Vertex::Pup(p), redundancy as u32)?;
|
|
g.add_edge(Vertex::Source, Vertex::Pdown(p), (self.replication_factor - redundancy) as u32)?;
|
|
for z in 0..nb_zones {
|
|
g.add_edge(Vertex::Pup(p) , Vertex::PZ(p,z) , 1)?;
|
|
g.add_edge(Vertex::Pdown(p) , Vertex::PZ(p,z) ,
|
|
self.replication_factor as u32)?;
|
|
}
|
|
}
|
|
for n in 0..self.useful_nodes().len() {
|
|
let node_capacity = self.get_node_capacity(&self.node_id_vec[n])?;
|
|
let node_zone = zone_to_id[&self.get_node_zone(&self.node_id_vec[n])?];
|
|
g.add_edge(Vertex::N(n), Vertex::Sink, node_capacity/size)?;
|
|
for p in 0..NB_PARTITIONS {
|
|
if !exclude_assoc.contains(&(p,n)) {
|
|
g.add_edge(Vertex::PZ(p, node_zone), Vertex::N(n), 1)?;
|
|
}
|
|
}
|
|
}
|
|
return Ok(g);
|
|
}
|
|
|
|
|
|
fn compute_candidate_assignment(&self, zone_to_id: &HashMap<String, usize>,
|
|
old_assoc_opt : &Option<Vec< Vec<usize> >>) -> Result<Graph<FlowEdge>, Error > {
|
|
|
|
//We list the edges that are not used in the old association
|
|
let mut exclude_edge = HashSet::<(usize,usize)>::new();
|
|
if let Some(old_assoc) = old_assoc_opt {
|
|
let nb_nodes = self.useful_nodes().len();
|
|
for p in 0..NB_PARTITIONS {
|
|
for n in 0..nb_nodes {
|
|
exclude_edge.insert((p,n));
|
|
}
|
|
for n in old_assoc[p].iter() {
|
|
exclude_edge.remove(&(p,*n));
|
|
}
|
|
}
|
|
}
|
|
|
|
//We compute the best flow using only the edges used in the old assoc
|
|
let mut g = self.generate_flow_graph(self.partition_size, zone_to_id, &exclude_edge )?;
|
|
g.compute_maximal_flow()?;
|
|
for (p,n) in exclude_edge.iter() {
|
|
let node_zone = zone_to_id[&self.get_node_zone(&self.node_id_vec[*n])?];
|
|
g.add_edge(Vertex::PZ(*p,node_zone), Vertex::N(*n), 1)?;
|
|
}
|
|
g.compute_maximal_flow()?;
|
|
return Ok(g);
|
|
}
|
|
|
|
fn minimize_rebalance_load(&self, gflow: &mut Graph<FlowEdge>, zone_to_id: &HashMap<String, usize>, old_assoc : &Vec< Vec<usize> >) -> Result<(), Error > {
|
|
let mut cost = CostFunction::new();
|
|
for p in 0..NB_PARTITIONS {
|
|
for n in old_assoc[p].iter() {
|
|
let node_zone = zone_to_id[&self.get_node_zone(&self.node_id_vec[*n])?];
|
|
cost.insert((Vertex::PZ(p,node_zone), Vertex::N(*n)), -1);
|
|
}
|
|
}
|
|
let nb_nodes = self.useful_nodes().len();
|
|
let path_length = 4*nb_nodes;
|
|
gflow.optimize_flow_with_cost(&cost, path_length)?;
|
|
|
|
return Ok(());
|
|
}
|
|
|
|
fn update_ring_from_flow(&mut self, nb_zones : usize, gflow: &Graph<FlowEdge> ) -> Result<(), Error>{
|
|
self.ring_assignation_data = Vec::<CompactNodeType>::new();
|
|
for p in 0..NB_PARTITIONS {
|
|
for z in 0..nb_zones {
|
|
let assoc_vertex = gflow.get_positive_flow_from(Vertex::PZ(p,z))?;
|
|
for vertex in assoc_vertex.iter() {
|
|
match vertex{
|
|
Vertex::N(n) => self.ring_assignation_data.push((*n).try_into().unwrap()),
|
|
_ => ()
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if self.ring_assignation_data.len() != NB_PARTITIONS*self.replication_factor {
|
|
return Err(Error::Message("Critical Error : the association ring we produced does not \
|
|
have the right size.".into()));
|
|
}
|
|
return Ok(());
|
|
}
|
|
|
|
|
|
//This function returns a message summing up the partition repartition of the new
|
|
//layout.
|
|
fn output_stat(&self , gflow : &Graph<FlowEdge>,
|
|
old_assoc_opt : &Option< Vec<Vec<usize>> >,
|
|
zone_to_id: &HashMap<String, usize>,
|
|
id_to_zone : &Vec<String>) -> Result<Message, Error>{
|
|
let mut msg = Message::new();
|
|
|
|
let nb_partitions = 1usize << PARTITION_BITS;
|
|
let used_cap = self.partition_size * nb_partitions as u32 *
|
|
self.replication_factor as u32;
|
|
let total_cap = self.get_total_capacity()?;
|
|
let percent_cap = 100.0*(used_cap as f32)/(total_cap as f32);
|
|
msg.push(format!("Available capacity / Total cluster capacity: {} / {} ({:.1} %)",
|
|
used_cap , total_cap , percent_cap ));
|
|
msg.push(format!(""));
|
|
msg.push(format!("If the percentage is to low, it might be that the \
|
|
replication/redundancy constraints force the use of nodes/zones with small \
|
|
storage capacities. \
|
|
You might want to rebalance the storage capacities or relax the constraints. \
|
|
See the detailed statistics below and look for saturated nodes/zones."));
|
|
msg.push(format!("Recall that because of the replication, the actual available \
|
|
storage capacity is {} / {} = {}.",
|
|
used_cap , self.replication_factor ,
|
|
used_cap/self.replication_factor as u32));
|
|
|
|
//We define and fill in the following tables
|
|
let storing_nodes = self.useful_nodes();
|
|
let mut new_partitions = vec![0; storing_nodes.len()];
|
|
let mut stored_partitions = vec![0; storing_nodes.len()];
|
|
|
|
let mut new_partitions_zone = vec![0; id_to_zone.len()];
|
|
let mut stored_partitions_zone = vec![0; id_to_zone.len()];
|
|
|
|
for p in 0..nb_partitions {
|
|
for z in 0..id_to_zone.len() {
|
|
let pz_nodes = gflow.get_positive_flow_from(Vertex::PZ(p,z))?;
|
|
if pz_nodes.len() > 0 {
|
|
stored_partitions_zone[z] += 1;
|
|
if let Some(old_assoc) = old_assoc_opt {
|
|
let mut old_zones_of_p = Vec::<usize>::new();
|
|
for n in old_assoc[p].iter() {
|
|
old_zones_of_p.push(
|
|
zone_to_id[&self.get_node_zone(&self.node_id_vec[*n])?]);
|
|
}
|
|
if !old_zones_of_p.contains(&z) {
|
|
new_partitions_zone[z] += 1;
|
|
}
|
|
}
|
|
}
|
|
for vert in pz_nodes.iter() {
|
|
if let Vertex::N(n) = *vert {
|
|
stored_partitions[n] += 1;
|
|
if let Some(old_assoc) = old_assoc_opt {
|
|
if !old_assoc[p].contains(&n) {
|
|
new_partitions[n] += 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if *old_assoc_opt == None {
|
|
new_partitions = stored_partitions.clone();
|
|
new_partitions_zone = stored_partitions_zone.clone();
|
|
}
|
|
|
|
//We display the statistics
|
|
|
|
msg.push(format!(""));
|
|
if *old_assoc_opt != None {
|
|
let total_new_partitions : usize = new_partitions.iter().sum();
|
|
msg.push(format!("A total of {} new copies of partitions need to be \
|
|
transferred.", total_new_partitions));
|
|
}
|
|
msg.push(format!(""));
|
|
msg.push(format!("Detailed statistics by zones and nodes."));
|
|
|
|
for z in 0..id_to_zone.len(){
|
|
let mut nodes_of_z = Vec::<usize>::new();
|
|
for n in 0..storing_nodes.len(){
|
|
if self.get_node_zone(&self.node_id_vec[n])? == id_to_zone[z] {
|
|
nodes_of_z.push(n);
|
|
}
|
|
}
|
|
let replicated_partitions : usize = nodes_of_z.iter()
|
|
.map(|n| stored_partitions[*n]).sum();
|
|
msg.push(format!(""));
|
|
|
|
msg.push(format!("Zone {}: {} distinct partitions stored ({} new, \
|
|
{} partition copies) ", id_to_zone[z], stored_partitions_zone[z],
|
|
new_partitions_zone[z], replicated_partitions));
|
|
|
|
let available_cap_z : u32 = self.partition_size*replicated_partitions as u32;
|
|
let mut total_cap_z = 0;
|
|
for n in nodes_of_z.iter() {
|
|
total_cap_z += self.get_node_capacity(&self.node_id_vec[*n])?;
|
|
}
|
|
let percent_cap_z = 100.0*(available_cap_z as f32)/(total_cap_z as f32);
|
|
msg.push(format!(" Available capacity / Total capacity: {}/{} ({:.1}%).",
|
|
available_cap_z, total_cap_z, percent_cap_z));
|
|
|
|
for n in nodes_of_z.iter() {
|
|
let available_cap_n = stored_partitions[*n] as u32 *self.partition_size;
|
|
let total_cap_n =self.get_node_capacity(&self.node_id_vec[*n])?;
|
|
let tags_n = (self.node_role(&self.node_id_vec[*n])
|
|
.ok_or("Node not found."))?.tags_string();
|
|
msg.push(format!(" Node {}: {} partitions ({} new) ; \
|
|
available/total capacity: {} / {} ({:.1}%) ; tags:{}",
|
|
&self.node_id_vec[*n].to_vec()[0..2].to_vec().encode_hex::<String>(),
|
|
stored_partitions[*n],
|
|
new_partitions[*n], available_cap_n, total_cap_n,
|
|
(available_cap_n as f32)/(total_cap_n as f32)*100.0 ,
|
|
tags_n));
|
|
}
|
|
}
|
|
|
|
return Ok(msg);
|
|
}
|
|
|
|
}
|
|
|
|
//====================================================================================
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
use std::io::*;
|
|
// use itertools::Itertools;
|
|
/*
|
|
fn check_assignation(cl: &ClusterLayout) {
|
|
//Check that input data has the right format
|
|
let nb_partitions = 1usize << PARTITION_BITS;
|
|
assert!(cl.ring_assignation_data.len() == nb_partitions * cl.replication_factor);
|
|
|
|
//Check that is is a correct assignation with zone redundancy
|
|
let rf = cl.replication_factor;
|
|
for i in 0..nb_partitions {
|
|
assert!(
|
|
rf == cl.ring_assignation_data[rf * i..rf * (i + 1)]
|
|
.iter()
|
|
.map(|nod| node_zone[*nod as usize].clone())
|
|
.unique()
|
|
.count()
|
|
);
|
|
}
|
|
|
|
let nb_nodes = cl.node_id_vec.len();
|
|
//Check optimality
|
|
let node_nb_part = (0..nb_nodes)
|
|
.map(|i| {
|
|
cl.ring_assignation_data
|
|
.iter()
|
|
.filter(|x| **x == i as u8)
|
|
.count()
|
|
})
|
|
.collect::<Vec<_>>();
|
|
|
|
let zone_vec = node_zone.iter().unique().collect::<Vec<_>>();
|
|
let zone_nb_part = zone_vec
|
|
.iter()
|
|
.map(|z| {
|
|
cl.ring_assignation_data
|
|
.iter()
|
|
.filter(|x| node_zone[**x as usize] == **z)
|
|
.count()
|
|
})
|
|
.collect::<Vec<_>>();
|
|
|
|
//Check optimality of the zone assignation : would it be better for the
|
|
//node_capacity/node_partitions ratio to change the assignation of a partition
|
|
|
|
if let Some(idmin) = (0..nb_nodes).min_by(|i, j| {
|
|
(node_capacity[*i] * node_nb_part[*j] as u32)
|
|
.cmp(&(node_capacity[*j] * node_nb_part[*i] as u32))
|
|
}) {
|
|
if let Some(idnew) = (0..nb_nodes)
|
|
.filter(|i| {
|
|
if let Some(p) = zone_vec.iter().position(|z| **z == node_zone[*i]) {
|
|
zone_nb_part[p] < nb_partitions
|
|
} else {
|
|
false
|
|
}
|
|
})
|
|
.max_by(|i, j| {
|
|
(node_capacity[*i] * (node_nb_part[*j] as u32 + 1))
|
|
.cmp(&(node_capacity[*j] * (node_nb_part[*i] as u32 + 1)))
|
|
}) {
|
|
assert!(
|
|
node_capacity[idmin] * (node_nb_part[idnew] as u32 + 1)
|
|
>= node_capacity[idnew] * node_nb_part[idmin] as u32
|
|
);
|
|
}
|
|
}
|
|
|
|
//In every zone, check optimality of the nod assignation
|
|
for z in zone_vec {
|
|
let node_of_z_iter = (0..nb_nodes).filter(|id| node_zone[*id] == *z);
|
|
if let Some(idmin) = node_of_z_iter.clone().min_by(|i, j| {
|
|
(node_capacity[*i] * node_nb_part[*j] as u32)
|
|
.cmp(&(node_capacity[*j] * node_nb_part[*i] as u32))
|
|
}) {
|
|
if let Some(idnew) = node_of_z_iter.min_by(|i, j| {
|
|
(node_capacity[*i] * (node_nb_part[*j] as u32 + 1))
|
|
.cmp(&(node_capacity[*j] * (node_nb_part[*i] as u32 + 1)))
|
|
}) {
|
|
assert!(
|
|
node_capacity[idmin] * (node_nb_part[idnew] as u32 + 1)
|
|
>= node_capacity[idnew] * node_nb_part[idmin] as u32
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
*/
|
|
|
|
fn show_msg(msg : &Message) {
|
|
for s in msg.iter(){
|
|
println!("{}",s);
|
|
}
|
|
}
|
|
|
|
fn update_layout(
|
|
cl: &mut ClusterLayout,
|
|
node_id_vec: &Vec<u8>,
|
|
node_capacity_vec: &Vec<u32>,
|
|
node_zone_vec: &Vec<String>,
|
|
) {
|
|
for i in 0..node_id_vec.len() {
|
|
if let Some(x) = FixedBytes32::try_from(&[i as u8; 32]) {
|
|
cl.node_id_vec.push(x);
|
|
}
|
|
|
|
let update = cl.roles.update_mutator(
|
|
cl.node_id_vec[i],
|
|
NodeRoleV(Some(NodeRole {
|
|
zone: (node_zone_vec[i].to_string()),
|
|
capacity: (Some(node_capacity_vec[i])),
|
|
tags: (vec![]),
|
|
})),
|
|
);
|
|
cl.roles.merge(&update);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_assignation() {
|
|
std::io::stdout().flush().ok().expect("Could not flush stdout");
|
|
let mut node_id_vec = vec![1, 2, 3];
|
|
let mut node_capacity_vec = vec![4000, 1000, 2000];
|
|
let mut node_zone_vec = vec!["A", "B", "C"]
|
|
.into_iter()
|
|
.map(|x| x.to_string())
|
|
.collect();
|
|
|
|
let mut cl = ClusterLayout {
|
|
node_id_vec: vec![],
|
|
|
|
roles: LwwMap::new(),
|
|
|
|
replication_factor: 3,
|
|
zone_redundancy: 1,
|
|
partition_size: 0,
|
|
ring_assignation_data: vec![],
|
|
version: 0,
|
|
staging: LwwMap::new(),
|
|
staging_hash: blake2sum(&rmp_to_vec_all_named(&LwwMap::<Uuid, NodeRoleV>::new()).unwrap()[..]),
|
|
};
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
show_msg(&cl.calculate_partition_assignation(3,3).unwrap());
|
|
assert!(cl.check());
|
|
|
|
node_id_vec = vec![1, 2, 3, 4, 5, 6, 7, 8, 9];
|
|
node_capacity_vec = vec![4000, 1000, 1000, 3000, 1000, 1000, 2000, 10000, 2000];
|
|
node_zone_vec = vec!["A", "B", "C", "C", "C", "B", "G", "H", "I"]
|
|
.into_iter()
|
|
.map(|x| x.to_string())
|
|
.collect();
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
show_msg(&cl.calculate_partition_assignation(3,3).unwrap());
|
|
assert!(cl.check());
|
|
|
|
node_capacity_vec = vec![4000, 1000, 2000, 7000, 1000, 1000, 2000, 10000, 2000];
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
show_msg(&cl.calculate_partition_assignation(3,3).unwrap());
|
|
assert!(cl.check());
|
|
|
|
node_capacity_vec = vec![4000000, 4000000, 2000000, 7000000, 1000000, 9000000, 2000000, 10000, 2000000];
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
show_msg(&cl.calculate_partition_assignation(3,1).unwrap());
|
|
assert!(cl.check());
|
|
|
|
}
|
|
}
|