Software /
code /
prosody
Annotate
util/hashring.lua @ 10688:83668e16b9a3
MUC: Switch to new storage format by default
Changing the default setting of `new_muc_storage_format` from false to true.
The code supports reading both formats since 0.11, but servers with MUCs stored
using the new format will not be able to downgrade to 0.10 or earlier.
The new format is clearer (less nesting for the most commonly-accessed data),
and combined with the new map-store methods, allows for some operations to become
more efficient (such as finding out which MUCs on a service a given user is affiliated
with).
author | Matthew Wild <mwild1@gmail.com> |
---|---|
date | Thu, 12 Mar 2020 16:10:44 +0000 |
parent | 10005:409ff72c501c |
child | 11208:96429946a742 |
rev | line source |
---|---|
10005
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
1 local function generate_ring(nodes, num_replicas, hash) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
2 local new_ring = {}; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
3 for _, node_name in ipairs(nodes) do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
4 for replica = 1, num_replicas do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
5 local replica_hash = hash(node_name..":"..replica); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
6 new_ring[replica_hash] = node_name; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
7 table.insert(new_ring, replica_hash); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
8 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
9 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
10 table.sort(new_ring); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
11 return new_ring; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
12 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
13 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
14 local hashring_methods = {}; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
15 local hashring_mt = { |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
16 __index = function (self, k) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
17 -- Automatically build self.ring if it's missing |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
18 if k == "ring" then |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
19 local ring = generate_ring(self.nodes, self.num_replicas, self.hash); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
20 rawset(self, "ring", ring); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
21 return ring; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
22 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
23 return rawget(hashring_methods, k); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
24 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
25 }; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
26 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
27 local function new(num_replicas, hash_function) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
28 return setmetatable({ nodes = {}, num_replicas = num_replicas, hash = hash_function }, hashring_mt); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
29 end; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
30 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
31 function hashring_methods:add_node(name) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
32 self.ring = nil; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
33 self.nodes[name] = true; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
34 table.insert(self.nodes, name); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
35 return true; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
36 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
37 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
38 function hashring_methods:add_nodes(nodes) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
39 self.ring = nil; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
40 for _, node_name in ipairs(nodes) do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
41 if not self.nodes[node_name] then |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
42 self.nodes[node_name] = true; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
43 table.insert(self.nodes, node_name); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
44 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
45 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
46 return true; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
47 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
48 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
49 function hashring_methods:remove_node(node_name) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
50 self.ring = nil; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
51 if self.nodes[node_name] then |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
52 for i, stored_node_name in ipairs(self.nodes) do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
53 if node_name == stored_node_name then |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
54 self.nodes[node_name] = nil; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
55 table.remove(self.nodes, i); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
56 return true; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
57 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
58 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
59 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
60 return false; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
61 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
62 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
63 function hashring_methods:remove_nodes(nodes) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
64 self.ring = nil; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
65 for _, node_name in ipairs(nodes) do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
66 self:remove_node(node_name); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
67 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
68 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
69 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
70 function hashring_methods:clone() |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
71 local clone_hashring = new(self.num_replicas, self.hash); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
72 clone_hashring:add_nodes(self.nodes); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
73 return clone_hashring; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
74 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
75 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
76 function hashring_methods:get_node(key) |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
77 local key_hash = self.hash(key); |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
78 for _, replica_hash in ipairs(self.ring) do |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
79 if key_hash < replica_hash then |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
80 return self.ring[replica_hash]; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
81 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
82 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
83 return self.ring[self.ring[1]]; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
84 end |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
85 |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
86 return { |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
87 new = new; |
409ff72c501c
util.hashring: Implementation of hashring data structure
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
88 } |