forked from Deuxfleurs/garage
Mendes
7f3249a237
It takes as paramters the replication factor and the zone redundancy, computes the largest partition size reachable with these constraints, and among the possible assignation with this partition size, it computes the one that moves the least number of partitions compared to the previous assignation. This computation uses graph algorithms defined in graph_algo.rs
814 lines
30 KiB
Rust
814 lines
30 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 serde::{Deserialize, Serialize};
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use garage_util::crdt::{AutoCrdt, Crdt, LwwMap};
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use garage_util::data::*;
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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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#[serde(default="default_one")]
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pub zone_redundancy: 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_zero")]
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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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pub staging: LwwMap<Uuid, NodeRoleV>,
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pub staging_hash: Hash,
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}
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fn default_one() -> usize{
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return 1;
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}
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fn default_zero() -> u32{
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return 0;
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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, zone_redundancy: usize) -> Self {
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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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zone_redundancy,
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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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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.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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/// 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,String> {
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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("The Uuid does not correspond to a node present in the cluster.".to_string())
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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,String> {
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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("The Uuid does not correspond to a node present in the cluster or this node does not have a positive capacity.".to_string())
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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,String> {
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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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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, replication:usize, redundancy:usize) -> Result<Message,String> {
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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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self.replication_factor = replication;
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self.zone_redundancy = 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.", replication, 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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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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//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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//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> > > ,String> {
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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(format!("There are more than {} non-gateway nodes in the new layout. This is not allowed.", MAX_NODE_NUMBER).to_string());
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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("The old assignation does not have a size corresponding to the old replication factor or the number of partitions.".to_string());
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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();
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//We add the indices of only the new non-gateway nodes that can be used in the
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//association ring
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for i in 0..nb_useful_nodes {
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uuid_to_new_id.insert(new_node_id_vec[i], i );
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}
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let rf= self.replication_factor;
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for p in 0..nb_partitions {
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for old_id in &self.ring_assignation_data[p*rf..(p+1)*rf] {
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let uuid = self.node_id_vec[*old_id as usize];
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if uuid_to_new_id.contains_key(&uuid) {
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old_assignation[p].push(uuid_to_new_id[&uuid]);
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}
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}
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}
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//We write the results
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self.node_id_vec = new_node_id_vec;
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self.ring_assignation_data = Vec::<CompactNodeType>::new();
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return Ok(Some(old_assignation));
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}
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///This function generates ids for the zone of the nodes appearing in
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///self.node_id_vec.
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fn generate_zone_ids(&self) -> Result<(Vec<String>, HashMap<String, usize>),String>{
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let mut id_to_zone = Vec::<String>::new();
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let mut zone_to_id = HashMap::<String,usize>::new();
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for uuid in self.node_id_vec.iter() {
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if self.roles.get(uuid) == None {
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return Err("The uuid was not found in the node roles (this should not happen, it might be a critical error).".to_string());
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}
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match self.node_role(&uuid) {
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Some(r) => if !zone_to_id.contains_key(&r.zone) && r.capacity != None {
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zone_to_id.insert(r.zone.clone() , id_to_zone.len());
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id_to_zone.push(r.zone.clone());
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}
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_ => ()
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}
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}
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return Ok((id_to_zone, zone_to_id));
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}
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///This function computes by dichotomy the largest realizable partition size, given
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///the layout.
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fn compute_optimal_partition_size(&self, zone_to_id: &HashMap<String, usize>) -> Result<u32,String>{
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let nb_partitions = 1usize << PARTITION_BITS;
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let empty_set = HashSet::<(usize,usize)>::new();
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let mut g = self.generate_flow_graph(1, zone_to_id, &empty_set)?;
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g.compute_maximal_flow()?;
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if g.get_flow_value()? < (nb_partitions*self.replication_factor).try_into().unwrap() {
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return Err("The storage capacity of he cluster is to small. It is impossible to store partitions of size 1.".to_string());
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}
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let mut s_down = 1;
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let mut s_up = self.get_total_capacity()?;
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while s_down +1 < s_up {
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g = self.generate_flow_graph((s_down+s_up)/2, zone_to_id, &empty_set)?;
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g.compute_maximal_flow()?;
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if g.get_flow_value()? < (nb_partitions*self.replication_factor).try_into().unwrap() {
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s_up = (s_down+s_up)/2;
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}
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else {
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s_down = (s_down+s_up)/2;
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}
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}
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return Ok(s_down);
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}
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fn generate_graph_vertices(nb_zones : usize, nb_nodes : usize) -> Vec<Vertex> {
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let mut vertices = vec![Vertex::Source, Vertex::Sink];
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for p in 0..NB_PARTITIONS {
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vertices.push(Vertex::Pup(p));
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vertices.push(Vertex::Pdown(p));
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for z in 0..nb_zones {
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vertices.push(Vertex::PZ(p, z));
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}
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}
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for n in 0..nb_nodes {
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vertices.push(Vertex::N(n));
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}
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return vertices;
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}
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fn generate_flow_graph(&self, size: u32, zone_to_id: &HashMap<String, usize>, exclude_assoc : &HashSet<(usize,usize)>) -> Result<Graph<FlowEdge>, String> {
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let vertices = ClusterLayout::generate_graph_vertices(zone_to_id.len(),
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self.useful_nodes().len());
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let mut g= Graph::<FlowEdge>::new(&vertices);
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let nb_zones = zone_to_id.len();
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for p in 0..NB_PARTITIONS {
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g.add_edge(Vertex::Source, Vertex::Pup(p), self.zone_redundancy as u32)?;
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g.add_edge(Vertex::Source, Vertex::Pdown(p), (self.replication_factor - self.zone_redundancy) as u32)?;
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for z in 0..nb_zones {
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g.add_edge(Vertex::Pup(p) , Vertex::PZ(p,z) , 1)?;
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g.add_edge(Vertex::Pdown(p) , Vertex::PZ(p,z) ,
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self.replication_factor as u32)?;
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}
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}
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for n in 0..self.useful_nodes().len() {
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let node_capacity = self.get_node_capacity(&self.node_id_vec[n])?;
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let node_zone = zone_to_id[&self.get_node_zone(&self.node_id_vec[n])?];
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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>, String > {
|
|
|
|
//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<(), String > {
|
|
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<(), String>{
|
|
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("Critical Error : the association ring we produced does not have the right size.".to_string());
|
|
}
|
|
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, String>{
|
|
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!("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;
|
|
}
|
|
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 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;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
//We display the statistics
|
|
|
|
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!(""));
|
|
|
|
if *old_assoc_opt != None {
|
|
msg.push(format!("Zone {}: {} distinct partitions stored ({} new, \
|
|
{} partition copies) ", id_to_zone[z], stored_partitions_zone[z],
|
|
new_partitions_zone[z], replicated_partitions));
|
|
}
|
|
else{
|
|
msg.push(format!("Zone {}: {} distinct partitions stored ({} partition \
|
|
copies) ",
|
|
id_to_zone[z], stored_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));
|
|
msg.push(format!(""));
|
|
|
|
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().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 itertools::Itertools;
|
|
|
|
fn check_assignation(cl: &ClusterLayout) {
|
|
//Check that input data has the right format
|
|
let nb_partitions = 1usize << PARTITION_BITS;
|
|
assert!([1, 2, 3].contains(&cl.replication_factor));
|
|
assert!(cl.ring_assignation_data.len() == nb_partitions * cl.replication_factor);
|
|
|
|
let (node_zone, node_capacity) = cl.get_node_zone_capacity();
|
|
|
|
//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 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() {
|
|
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,
|
|
ring_assignation_data: vec![],
|
|
version: 0,
|
|
staging: LwwMap::new(),
|
|
staging_hash: sha256sum(&[1; 32]),
|
|
};
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
cl.calculate_partition_assignation();
|
|
check_assignation(&cl);
|
|
|
|
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);
|
|
cl.calculate_partition_assignation();
|
|
check_assignation(&cl);
|
|
|
|
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);
|
|
cl.calculate_partition_assignation();
|
|
check_assignation(&cl);
|
|
|
|
node_capacity_vec = vec![4000, 4000, 2000, 7000, 1000, 9000, 2000, 10, 2000];
|
|
update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
|
|
cl.calculate_partition_assignation();
|
|
check_assignation(&cl);
|
|
}
|
|
}
|