This session at Unite Copenhagen focused on Multiplay's new matchmaking service that allows developers to create their own custom matchmaking logic. Get a glimpse into how matchmaking works with Multiplay's game server hosting to accelerate on-boarding onto this powerful platform. Speakers: Josie Messa – Unity Caleb Atwood – Unity

1. Advanced Matchmaking
with Multiplay
1
Josie Messa & Caleb Atwood

2. Multiplay
Josie Messa
Backend Developer

3. What Do Multiplay Do?
3
— Specialise in hosting real-time multiplayer games
— Hybrid scaling
— Resource orchestration platform

4. Allocations
4

5. Matchmaker wants to host a game session
Allocate Request
5
Makes an “allocate” request to Multiplay’s
APIs for a game server
Matchmaker Multiplay
/server/allocate

6. Allocate Request
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
// REQUEST
$ curl -X POST /server/allocate?
profileid=104843
regionid=375ed04b-a4c2-4ecb-91ab-9ebc27eafbb0
uuid=2f139030-e997-11e8-9f32-f2801f1b9fd1
fleetid=7db01ecd-68f9-45ff-8f1e-369b2b4e4913
// RESPONSE
{
"allocation": {
"profileid": 1075753,
"uuid": "2f139030-e997-11e8-9f32-f2801f1b9fd1",
"regions": "375ed04b-a4c2-4ecb-91ab-9ebc27eafbb0",
"requested": "2019-09-24T15:05:16.601951875Z",
"created": "2019-09-24T15:05:16.601951875Z",
"fleetid": "7db01ecd-68f9-45ff-8f1e-369b2b4e4913"
}
}
6

7. Party Servers
Fleets
7
— Fleets are a logical group of
servers.
— Servers belong to a fleet.
— Allocations and scaling are made
within a fleet.
Game Servers

8. Regions
8
— Defined based on player density.
— Bare metal and cloud availability
zones, allow for burst scaling.

9. Specifies details about the server the game
should be hosted on.
Used for switching versions.
Other Parameters
9
Used to track allocation throughout its
lifecycle.
Generated by matchmaker for idempotency.
Profile Allocation UUID

10. Allocating Servers

11. Servers on Machines
Players
Server
Server
Server
Machine

12. Allocating Servers
Bare Metal
Cloud

13. Allocating Servers
Server
Server
Server
Server
Server
Server
Server
Server
Server
cost

14. Allocating Servers
Server
Server
Server
Server
Server
Server
Server
Server
Server
Hot machine
cost

15. Profiles
Profile BProfile A
# Already running (not allocated)
$ ./server -gamemode=casual
# Start up on new profile
$ ./server -gamemode=ranked
SIGTERM

16. Matchmaker polls allocations endpoint with
the allocation UUID to check status
Allocations Request
16
Multiplay responds with the allocation when
the server is ready.
Matchmaker Multiplay
/server/allocations

17. {Server Details}
Matchmaker
Matchmaker now has details of the server to
host the game session
Allocations Request
17
This can be passed to the client so it can
directly connect to the game server.
Game Client

18. Game server tells matchmaker it’s ready to
deallocate, matchmaker calls us
Deallocate Request
18
We remove the allocation from our system
and refresh the server configuration.
Matchmaker Multiplay
/server/deallocate

19. Scaling

20. Scaling Method
Bare Metal

21. Scaling Method
Server
Server
Server
Server
Server
Server
Server
Server
Server
Unused Machine
cost

22. Matchmaker Integration

23. — How is the game server connection information passed to the clients?
— How do solve for player density across regions?
— How are custom requirements configured, such as map/mode?
— What concerns does the game server have in accepting new matches?
— When is a deallocation processed?
Questions for Matchmaker Design

24. Matchmaking
Caleb Atwood
Tech Lead

25. Multiplay Matchmaking
Beta
25
Fall for Multiplay customers

26. Matchmaking from 10,000 feet
26

27. Matchmaking from 10,000 feet
27
Game Client Matchmaking
/tickets
Players want to play Matchmaking finds “good"
groups of players waiting for
games to play together
Multiplay
/allocate
assignment ip:port
Matchmaking asks
Multiplay for a server
for the new game

28. Matchmaking from 1,000 feet
28
CLI
1
Game Server
1
Game Server
Game
Server
Game Client
InternalAPI
BackendAPI
Orchestration
Match
Function
Hosting
Matchmaker
MatchmakingAPI
Director
SDK
Skill, Party,
Player Data
1
Analytics
Configuration
Identity, QoS
Services
Custom
SkillFunc
Custom
CasualFunc
Backfill
LobbyService
SDK

29. Matchmaking 2 feet off the ground going 640kph
29
What is it?
— Open Match
— Tickets: { Attributes, Properties, Assignments }
— Match Functions: { Concurrency, Query, Algorithms, Proposals, Development }
— Evaluation: { Score Normalization }
— Configuration: { Functions, Pools, Scaling, Multiplay }
How do you use it?
— Matchmaking as backend infrastructure
— Practical Matchmaking (but wait, how do I…?)

30. Open Match
30
● openmatch.dev
● openmatch.dev/site/docs/
● github.com/googleforgames/open-match
● open-match.slack.com
Roadmap
- V0.6 - github.com/googleforgames/open-match/releases/tag/v0.6.0
- V0.7
- Advanced player data indexing
- Enhanced filtering api [bool, string]
- Automated stress testing
- Performance improvements
- Improved tutorials and demo code
- Monitoring Metrics

31. Tickets
31

32. Attributes
Tickets
32
— { Attributes, Properties, Assignments }
— Assignment = the ticket’s final state
– Connection details
– Custom assignment properties
– Assignment/matchmaking errors.
Properties
Skill / TeamSkill
PlayerCount
Mode
Rank
Client Version
Keys Held
Role
Recent History
Friends Online
Cars Unlocked
QoS Data
Inventory

33. Tickets
33
{
"attributes": {
"mode": 1,
"teamSkill": 2437,
"playerCount": 2
},
"properties": {
"partyInfo": {
"partyId": 21398712387,
"players": ["caleb", "josie"],
"recentMatch": [ 987219387123, 1298723198371 ]
},
"qosConnection":[
{ "location": "2183", "avePing": 83, "quality": 12 },
{ "location": "4128", "avePing": 67, "quality": 4 }
],
"mapsUnlocked": [ "dust", "moon", "unite" ]
}
}

34. Match Functions
34

35. Match Functions
35
Code you write to fetch and group tickets into proposals
- Tooling for local simulation and testing
- Api for management through CLI
- Api to get logs from your running functions
- Examples: QoS, Skill Balance, Backfill, Timeout, Recent Matchup Avoidance

36. Match Functions
36
1. Construct and run a query
2. Group players together based on their ticket data to generate proposals
3. Decorate proposals with additional data
a. For the game server (mode, map, teams)
b. For the tickets (team, role)
c. Set any overrides if applicable (previously existing host)
4. Score and return the proposals

37. Querying for Tickets by Attribute Data

38. - Multiple-priority role preferences - healer AND/OR tank
- Social graph distances - friends of friends dynamic runtime lookup
- Conditional attribute weighting - xp only matters if skill confidence is weak
- Scheduled specialized content access - 2 hour window for rare-boss matches
- Geo-distance - combinations of multiple parameters into new parameters
- Off-box calls - reasonable if fast(consider preemptable indexing instead)
- Simulated functions - production sandbox for testing new algorithms
- Outcome prediction - build your own quality confidence
Match Function Customizations
Wall. of. text.

39. Configuration
39

40. Configuration
40
Multiplay
- profileId
- key
Matchmaking (generator)
- name
- targetFunction
- config
- pools
{
"matchmaking": {
"name": "ctf-competitive",
"targetFunction": {
"name": "team-skill-function"
},
"pools": {
"default": [
{
"attribute": "skill",
"min": 0,
"max": 3000
}
]
},
"config": {
"teamCount": 2,
"teamMin": 3,
"teamMax": 4
}
},
"multiplay":{
"profileId": "",
"key": ""
}
}

41. Configuration
41
More tickets
slows things down
Just do MORE
{
"matchmaking" : {
"name": "ctf-competitive" ,
"targetFunction" : {
"name":
"team-skill-function"
},
"pools": {
"default": [
{
"attribute": "skill",
"min": 0,
"max": 1600
}
]
},
"config": { … }
},
"Multiplay" :{ … }
}
{
"matchmaking" : {
"name": "ctf-competitive" ,
"targetFunction" : {
"name":
"team-skill-function"
},
"pools": {
"default": [
{
"attribute": "skill",
"min": 1400,
"max": 3000
}
]
},
"config": { … }
},
"Multiplay" :{ … }
}

42. Configuration
42
Automate “MORE”
DistributionTypes
- Normal
- Uniform
- LinearApproximation
- Auto
BehaviorTypes
- BucketCount
- BucketSize
{
"matchmaking" : {
"name": "ctf-competitive" ,
"targetFunction" : {
"name": "team-skill-function"
},
"pools": {
"default": [
{
"attribute": "skill",
"min": 0,
"max": 3000,
"segmentation":{
"distributionType": "Normal",
"segmentBehaviorType": "BucketCount",
"segmentSize": 10
}
}
]
},
"config": { … }
},
"multiplay" :{ … }
}

43. Visualizing what’s happening
team-function
timeout-function
Configs
ctf-competitive
ctf-social
global-timeout
Director
? Accepted
Matches

44. Evaluation
44
?

45. Evaluation
Concurrent Match Functions = Ticket 124a3ew can appear in multiple proposals
124a3ew
198e31j
lj34093
1oj412l2
124a3ew
834jl1j3
vs

46. Evaluation
46
Concurrent Match Functions = Ticket 124a3ew can appear in multiple proposals
We want to normalize our Score across functions. In our case, we’re using a
RootMeanSquaredDeviation calculation with weights to create a score algorithm.
0.5f * RMSD(time-waiting) + 0.5f * 1/RMSD(skill-gap)
124a3ew s=90 t=134
198e31j s=80 t=35
lj34093 s=88 t=210
Score = 115.7
1oj412l2 s=99 t=350
124a3ew s=90 t=134
834jl1j3 s=30 t=198
Score = 146.8
vs

47. But How Do I...?
Just do matchmaking?
Support multiple playlists?
Securely put player data (e.g. skill) into tickets?
Do Quality of Service based matchmaking to nearby regions?
Parties?
Backfill?
What about peer to peer?

48. Quick Reminder
48
CLI
1
Game Server
1
Game Server
Game
Server
Game Client
InternalAPI
BackendAPI
Orchestration
Match
Function
Hosting
Matchmaker
MatchmakingAPI
Director
SDK
Skill, Party,
Player Data
1
Analytics
Configuration
Identity, QoS
Services
Custom
SkillFunc
Custom
CasualFunc
Backfill
LobbyService
SDK

49. 1
Game Server
Quick Reminder
49
1
Game Server
1
Game Server
Multiplay
Game Client
MatchmakingAPI
Configs
SDK
Player Data
Services
Game Client
Services
Func 1
Func 2
Backfill
LobbyService

50. 50
Game Client
SDK
Remote Config Func 1
Func 2
{
"attributes": {
"mode": 2, ...
},
"properties": {...}
}
Configs
"attribute": "mode",
"min": 2,
"max": 2
Playlists?

51. Secure Player Data
51
Game Client
MatchmakingAPI
SDK
Player Data
Services
LobbyService
Identity

52. Region Based?
52
1
Game Server
1
Game Server
Region A Server
Multiplay
Game Client
MatchmakingAPI
SDK
QoS Discovery Func 1
------------
-Query tickets
-Categories by region
connections
-Matchmake within
best regions for tickets
-Set region on proposal
LobbyService
Automatically
/allocate
region A
QoS Discovery

53. Parties?
53
Game Client
SDK
Friends/Invites
Sessions
LobbyService
Identity
{
"attributes": {
"playerCount": 2, ...
},
"properties": {...playerData...}
}

54. 1
Game Server
Backfill? Option 1: Function
54
1
Game Server
1
Game Server
Multiplay
Configs
Func 1
Func 2
Backfill
Backfill
Function
Game Client
MatchmakingAPI
SDK
LobbyService
"proposal.properties.ConnectionOverride":
"179.82.03.29:475",

55. 1
Game Server
Backfill? Option 2: Ticket
1
Game Server
1
Game Server
Multiplay
Configs
Func 1
Host-Pool Enabled
Func 2
Host-Pool Enabled
Backfill
MatchmakingAPI
"connectionOverride":
"179.82.03.29:475",
"targetFunction": {
"name": "func1"
},
"pools":{
"default":[{...}],
"servers": [
{"attribute": "host",}
],
},
{
"attributes": {
"host": true, ...
},
"properties": {...currentPlayers...}
}

56. Configs
Func 1
Host-Pool Enabled
Func 2
Host-Pool Enabled
MatchmakingAPI
"connectionOverride":
"179.82.03.29:475",
"targetFunction": {
"name": "func1"
},
"pools":{
"default":[{...}],
"servers": [
{"attribute": "host",}
],
},
{
"attributes": {
"host": true,
},
"properties": {
"conn":
"179.82.03.29:475",
},
}
Peer to Peer?

57. Reference Slides After This

58. Closing
Deeply custom
matchmaking logic
Integrates automatically
with Multiplay
Multiplay Matchmaking
Beta this Fall (soon)

59. Other Talks
Yesterday - Hosting Happy Gamers
Today @ 4:00pm - How MADFINGER is leading next-gen multiplayer mobile FPS game
Today @ 12:00 pm - How the Apex Legends Season 2 online experience was scaled
Tomorrow @ 2:30pm - Voice and text comms for Unity: using Vivox to connect your
players

60. Questions?
Got a question about the Multiplay
matchmaker or Multiplay’s game
server hosting?
https://multiplay.com/contactus/