Migration of cluster layout from v0.8 to v0.9

This commit is contained in:
Alex 2023-01-11 17:47:46 +01:00
parent 4f409f73dc
commit 84b4a868e3
Signed by untrusted user: lx
GPG key ID: 0E496D15096376BE

View file

@ -5,8 +5,6 @@ use std::collections::HashSet;
use bytesize::ByteSize;
use itertools::Itertools;
use serde::{Deserialize, Serialize};
use garage_util::crdt::{AutoCrdt, Crdt, Lww, LwwMap};
use garage_util::data::*;
use garage_util::encode::nonversioned_encode;
@ -23,76 +21,196 @@ const NB_PARTITIONS: usize = 1usize << PARTITION_BITS;
// The Message type will be used to collect information on the algorithm.
type Message = Vec<String>;
/// The layout of the cluster, i.e. the list of roles
/// which are assigned to each cluster node
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct ClusterLayout {
pub version: u64,
mod v08 {
use crate::ring::CompactNodeType;
use garage_util::crdt::LwwMap;
use garage_util::data::{Hash, Uuid};
use serde::{Deserialize, Serialize};
pub replication_factor: usize,
/// The layout of the cluster, i.e. the list of roles
/// which are assigned to each cluster node
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct ClusterLayout {
pub version: u64,
/// This attribute is only used to retain the previously computed partition size,
/// to know to what extent does it change with the layout update.
pub partition_size: u64,
/// Parameters used to compute the assignment currently given by
/// ring_assignment_data
pub parameters: LayoutParameters,
pub replication_factor: usize,
pub roles: LwwMap<Uuid, NodeRoleV>,
pub roles: LwwMap<Uuid, NodeRoleV>,
/// node_id_vec: a vector of node IDs with a role assigned
/// in the system (this includes gateway nodes).
/// The order here is different than the vec stored by `roles`, because:
/// 1. non-gateway nodes are first so that they have lower numbers
/// 2. nodes that don't have a role are excluded (but they need to
/// stay in the CRDT as tombstones)
pub node_id_vec: Vec<Uuid>,
/// the assignation of data partitions to node, the values
/// are indices in node_id_vec
#[serde(with = "serde_bytes")]
pub ring_assignation_data: Vec<CompactNodeType>,
/// node_id_vec: a vector of node IDs with a role assigned
/// in the system (this includes gateway nodes).
/// The order here is different than the vec stored by `roles`, because:
/// 1. non-gateway nodes are first so that they have lower numbers holding
/// in u8 (the number of non-gateway nodes is at most 256).
/// 2. nodes that don't have a role are excluded (but they need to
/// stay in the CRDT as tombstones)
pub node_id_vec: Vec<Uuid>,
/// the assignment of data partitions to node, the values
/// are indices in node_id_vec
#[serde(with = "serde_bytes")]
pub ring_assignment_data: Vec<CompactNodeType>,
/// Role changes which are staged for the next version of the layout
pub staging: LwwMap<Uuid, NodeRoleV>,
pub staging_hash: Hash,
}
/// Parameters to be used in the next partition assignment computation.
pub staging_parameters: Lww<LayoutParameters>,
/// Role changes which are staged for the next version of the layout
pub staging_roles: LwwMap<Uuid, NodeRoleV>,
pub staging_hash: Hash,
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct NodeRoleV(pub Option<NodeRole>);
/// The user-assigned roles of cluster nodes
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct NodeRole {
/// Datacenter at which this entry belong. This information is used to
/// perform a better geodistribution
pub zone: String,
/// The capacity of the node
/// If this is set to None, the node does not participate in storing data for the system
/// and is only active as an API gateway to other nodes
pub capacity: Option<u64>,
/// A set of tags to recognize the node
pub tags: Vec<String>,
}
impl garage_util::migrate::InitialFormat for ClusterLayout {}
}
impl garage_util::migrate::InitialFormat for ClusterLayout {}
/// This struct is used to set the parameters to be used in the assignment computation
/// algorithm. It is stored as a Crdt.
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct LayoutParameters {
pub zone_redundancy: usize,
mod v09 {
use super::v08;
use crate::ring::CompactNodeType;
use garage_util::crdt::{Lww, LwwMap};
use garage_util::data::{Hash, Uuid};
use serde::{Deserialize, Serialize};
pub use v08::{NodeRole, NodeRoleV};
/// The layout of the cluster, i.e. the list of roles
/// which are assigned to each cluster node
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct ClusterLayout {
pub version: u64,
pub replication_factor: usize,
/// This attribute is only used to retain the previously computed partition size,
/// to know to what extent does it change with the layout update.
pub partition_size: u64,
/// Parameters used to compute the assignment currently given by
/// ring_assignment_data
pub parameters: LayoutParameters,
pub roles: LwwMap<Uuid, NodeRoleV>,
/// see comment in v08::ClusterLayout
pub node_id_vec: Vec<Uuid>,
/// see comment in v08::ClusterLayout
#[serde(with = "serde_bytes")]
pub ring_assignment_data: Vec<CompactNodeType>,
/// Parameters to be used in the next partition assignment computation.
pub staging_parameters: Lww<LayoutParameters>,
/// Role changes which are staged for the next version of the layout
pub staging_roles: LwwMap<Uuid, NodeRoleV>,
pub staging_hash: Hash,
}
/// This struct is used to set the parameters to be used in the assignment computation
/// algorithm. It is stored as a Crdt.
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Debug, Serialize, Deserialize)]
pub struct LayoutParameters {
pub zone_redundancy: usize,
}
impl garage_util::migrate::Migrate for ClusterLayout {
const VERSION_MARKER: &'static [u8] = b"Glayout09";
type Previous = v08::ClusterLayout;
fn migrate(previous: Self::Previous) -> Self {
use itertools::Itertools;
use std::collections::HashSet;
// In the old layout, capacities are in an arbitrary unit,
// but in the new layout they are in bytes.
// Here we arbitrarily multiply everything by 1G,
// such that 1 old capacity unit = 1GB in the new units.
// This is totally arbitrary and won't work for most users.
let cap_mul = 1024 * 1024 * 1024;
let roles = multiply_all_capacities(previous.roles, cap_mul);
let staging_roles = multiply_all_capacities(previous.staging, cap_mul);
let node_id_vec = previous.node_id_vec;
// Determine partition size
let mut tmp = previous.ring_assignation_data.clone();
tmp.sort();
let partition_size = tmp
.into_iter()
.dedup_with_count()
.map(|(npart, node)| {
roles
.get(&node_id_vec[node as usize])
.and_then(|p| p.0.as_ref().and_then(|r| r.capacity))
.unwrap_or(0) / npart as u64
})
.min()
.unwrap_or(0);
// Determine zone redundancy parameter
let zone_redundancy = std::cmp::min(
previous.replication_factor,
roles
.items()
.iter()
.filter_map(|(_, _, r)| r.0.as_ref().map(|p| p.zone.as_str()))
.collect::<HashSet<&str>>()
.len(),
);
let parameters = LayoutParameters { zone_redundancy };
let mut res = Self {
version: previous.version,
replication_factor: previous.replication_factor,
partition_size,
parameters,
roles,
node_id_vec,
ring_assignment_data: previous.ring_assignation_data,
staging_parameters: Lww::new(parameters),
staging_roles,
staging_hash: [0u8; 32].into(),
};
res.staging_hash = res.calculate_staging_hash();
res
}
}
fn multiply_all_capacities(
old_roles: LwwMap<Uuid, NodeRoleV>,
mul: u64,
) -> LwwMap<Uuid, NodeRoleV> {
let mut new_roles = LwwMap::new();
for (node, ts, role) in old_roles.items() {
let mut role = role.clone();
if let NodeRoleV(Some(NodeRole {
capacity: Some(ref mut cap),
..
})) = role
{
*cap = *cap * mul;
}
new_roles.merge_raw(node, *ts, &role);
}
new_roles
}
}
pub use v09::*;
impl AutoCrdt for LayoutParameters {
const WARN_IF_DIFFERENT: bool = true;
}
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct NodeRoleV(pub Option<NodeRole>);
impl AutoCrdt for NodeRoleV {
const WARN_IF_DIFFERENT: bool = true;
}
/// The user-assigned roles of cluster nodes
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct NodeRole {
/// Datacenter at which this entry belong. This information is used to
/// perform a better geodistribution
pub zone: String,
/// The capacity of the node
/// If this is set to None, the node does not participate in storing data for the system
/// and is only active as an API gateway to other nodes
pub capacity: Option<u64>,
/// A set of tags to recognize the node
pub tags: Vec<String>,
}
impl NodeRole {
pub fn capacity_string(&self) -> String {
match self.capacity {