Unity Multiplayer Mirror - Open Source Networking for Unity

Hey, this could very well be user error but I've noticed that the mirror network loop is taking up half of my frame time. Could this be caused perhaps by my possible misuse of mirror's API or is this just the nature of the beast that is mirror?
Note - I am the host in this scenario with no other clients connected.

Also, looking forward to that blog post for Mirror II

 

Why is your deep profile button grayed out?
If you enable it, then you can see more details.

 

Found the issue, thanks very much! Didn't realise that would expand the Network Loop!

 

Mirror II Cmds/Rpcs/TargetRpcs finished!
17.000 LOC into it, it now has enough features where projects like uMMORPG could already be ported
Early access in ~1 month.

 

Made with Mirror: Sun Haven.

 

Running a dedicated server within wsl (using tanks demo), clients can't connect to it (it is working fine when running the same exact dedicated server build on native ubuntu). Any ideas why this might be happening?

 

I have a question. How does one detect if the server is also a client? That is, whether we're running in "dedicated server" or "host server" mode. A user said we can use:

if (NetworkServer.active)

Does that only return true on the client that is a server, or on all clients?

Thanks,
-Brian

 

you can check like this:

Code (CSharp):

1.  
2. if (NetworkServer.active && NetworkClient.active)
3. {
4.   // do host mode stuff here
5. }

NetworkServer.active will be true in both server only and host mode

 

Excellent, thanks!

 

Mirror 2 progress update.
Deep profiling to prepare for the CCU test.
Afterwards documentation, examples and then release

Quite happy with the profiling results so far.
It's nice that LocalWorldState packing + Delta Compression + Reliability + Send + Recv are all gone from main thread.

 

Mirror 2 Remote Control to prepare for the CCU test.
Tick rate shows actual / target frequency.
CPU shows early / late update averages.


Here's a video:
https://gyazo.com/1234d93038cbae1ff6e8d39e49dcc449

Will be very useful for the CCU test, so we can see when the individual threads get full, or how much room there is until actual tick rate drifts below target tick rate.

 

Hi! I hope this is the right place to post this question.

My team and I are trying to connect Unity Relay (that uses Unity Transport) with Mirror. For this, it seems that we need to implement Mirrors abstract class "Transport". We are looking for any guidance, documentation or samples to help us with this task, but we are not having any luck.

I asked a question in this other thread about a mysterious sample that theoretically exists but we cannot find it anywhere:
Connecting Unity Transport (using Unity Relay) with Mirror - Unity Forum

Any help would be enormously appreciated!

 

Check out the #epic Transport in our Discord.
It's a free relay thanks to Epic Online Services' success with Fortnite, and it works well.

 

Does Mirror allowed for host migration?

 

just wondering how do you deal with orchestration is there any providers we can use mirror networking with?

 

UNET used to have host migration when we forked it.
It was always broken and super complex, so we decided to remove it for the sake of stability.
Probably best to host dedicated servers if you need to.

Google cloud, AWS, Multiplay etc

 

Mirror II nearing release!

Preparing for the CCU test.
The setup will be built in, for everyone to reproduce.
Will compare it against original Mirror first.
Gonna set up some bots + servers this weekend and get the first results.

Quite happy how it all turned out.
Much more pleasant to work with than UNET back then.
Both for stability, performance, code complexity etc.
Dunno if you guys are gonna like it, but I really am looking forward to using this for my two projects


Video:
https://gyazo.com/c4e639f8a2416cb918690f5c1c6a8491

 

Hi, vis2k.

I'm just wondering if the Mirror dev team is planning on adding a built-in framework for client-side prediction and server reconciliation. It seems like other solutions such as FishNet and Netcode for GameObjects are starting to adopt this as a feature, and it would be really nice for it to come to Mirror as well, as it's one of the most vital features for a smooth and secure multiplayer experience. I and many others would really benefit from this feature being added.

Is this something you're looking to add in the future? Is this something that might be added with Mirror 2?

Thanks for your time.

 

When we started using UNET for our games, the two main issues stopping us from releasing were stability and scale.

• Mirror solved stability, and improved scale quite a bit.
• DOTSNET and now Mirror II exist to solve scale.

Lack of client side prediction hasn't stopped us from releasing, so it was never a focus.
For my MMO project, I manually predict movement & skill effects. It's just not built into Mirror.

I understand it's important for some people.
But let's solve scale first

 

Yeah, I understand. Do you feel like it's something that you may add once you have scaling in the place you want it to be, even if that may be a few years in the future? I feel like it would be a good thing to keep in the back of your mind and then work on implementing once you feel like you're happy with the state of current features and stability, and are ready to expand.

 

I've been working on CSP for my fork of mirror. It has all the main parts but I am working on improving and optimizing it before I release it (and probably make a mirror version)

 

That would be awesome! I would love to use it once you release it.

 

Early CCU tests for Mirror II.

Goal is to compare with original Mirror to see scale & bandwidth improvements.
Keep in mind that this is not a real game. I'll do a more realistic test for my own game in ~6 months.
Original Mirror results with same demo coming later this week.

Setup:

• 1 x 16 vCPU server machine.
• 6 x 8-16 vCPU client machines.
• Unity 2021.3.9, IL2CPP.
• Linux.
• Threaded Transport (1 KCP thread).
• Threaded Broadcaster (10 Broadcaster threads).
• tickRate: 30 Hz
• sendRate: 30 Hz
• 10.000 monsters (red), moving randomly.
• 0-1000 players (white), moving randomly.

Results:
Broadcaster avg. is at around 30% load, indicating that 3 threads would've been enough for 1000 connections.
Tick rate starts deviating from target 30 Hz at around 800 connections.
Quite happy that it passed with 0 issues.

0 connections:


400 connections:


1000 connections:

 

CCU Test Mirror classic vs. Mirror II

400 CCU Mirror classic:
bandwidth: 7.66 MB/s
cpu: 31.7 ms



400 CCU Mirror II:
bandwidth: 1,74 MB/s (4.4x lower)
cpu: 21.7ms (slows down at 800, allows 2x scale)



Summary: 4.4x lower bandwidth, 2x higher scale.
Quite happy with the results, considering it's the first version and very first test

 

CCU Test Mirror II on dedicated Xeon E-2236 with 6 cores/ 12 threads @ 3.4 GHz (4.8 GHz).

Google Cloud vCPU server: 40.6 ms
Dedicated Xeon: 33.8ms

=> 20% faster.
=> almost manages to retain target tickRate of 30 Hz.

So if you were wondering: real dedicated CPUs can be ~20% faster than Google Cloud vCPUs

 

Good to see the new update. This update should follow with new tutorials for new users.
Thank you.

 

Sure.
The next 1-2 weeks will be focused on documentation + performance tests.

 

Hi, I need to have a centralised server which relays the game objects data and forwards to different devices, there is a way to do it (eg: installing the library server app on a remote server)?

I would like to have only two VR visors watch each other movements and audio chat between them.

 

check out the #epic transport in our discord.
free relay thanks to epic games

 

I updated Mirror to 2022.9.15 and now i'm getting errors. Four "type or namespace name" not found. This is with a fresh project too. Any solutions to this?

 

Please post the full stack trace + error here. That's what they are made for

 

Update: instead of releasing Mirror II this week, we will backport many of the improvements to Mirror.
There is too much value that can be added to all the existing projects, Mirror II can wait
Afterwards do another round of CCU tests and re-evaluate.

Simplifying OnSerialize today, where previously it would need a bool return.
This was changed to void to a-void confusion and reduce branching for performance.
Also simplifies weaver generated code:

 

News: Snapshot Interpolated Timeline


Previously, NetworkTime and each(!) NetworkTransform would run on separate timelines.

Now, everything runs on the same NetworkClient timeline, thanks to our Snapshot Interpolation V2.
-> Less computations & complexity
-> All NetworkTransforms are now on the same time, instead of each being on their own time
-> NetworkTime is now implemented properly via Snapshot Interpolation. This is noticeably more accurate. There's no more big jump in the first 1-3s.

This is one of those improvements which required months of research & testing, yet most of you won't even notice it other than the fact that it just works

 

Bandwidth optimizations, first round.

NetworkIdentity.Serialize bandwidth reduced from 1 byte per component index to (roughly) 1 bit per component
https://github.com/vis2k/Mirror/pull/3228

before / after:


the removed byte per component:

 

Bandwidth optimizations, second round.

NetworkBehaviour.Serialize 'length' safety reduced from 4 bytes per component to 1 byte per component.

Error correction remains(!). Never wanted to do the 'barrier' solution, as that loses the built in error correction. Took me several years to think of a better solution, but I think this is quite nice

https://github.com/vis2k/Mirror/pull/3229

 

Anybody know how I could get a legacy version of Mirror compatible with Unity 2019.4?

 

You can try one of the older releases on our github releases page.
Considering to add in the obsolete parts for 2019 support again though. Many people kept asking for it.

 

Mirror is now compatible with Unity 2019, 2020, 2021 again!
Get it from Github if you need 2019 / 2020 support today

 

Does anyone know how to fix this? I tried importing Mirror into an empty project and was hit with these four error. i tried redownloading and re importing but nothing changed.

 

See my above post.
Mirror is now compatible with 2019/2020 again.
Download it from github

 

sweet that solved it, thank you!

 

Hi !

I'm currently using Mirror Networking to make a multiplayer game. I have a scene when players are all connected, they can choose their characters and set the ready. If all players are ready, I change current scene to arena scene using MyNetworkManager.ServerChangeScene(arenaSceneName). This method sets all player clients as not ready. But After the scene was loaded, my player client is no longer connected to my host and I don't know why.

Can you help me please ?

Thanks a lot for answers.

 

Please check out the build in scene examples.
I think MrGadget made one that does just that.

 

I didn't find it.

 

SyncDirection released.

NetworkBehaviour OnSerialize can now be directed either from server to client, or from client to server.
For example, this will allow us develop NetworkTransform V3 without Rpc/Cmd call overhead for client authority, where previously OnSerialize couldn't be used since it was only going in one direction

Note this means that any component can now run in what's known as "client authority" mode. However, you can still validate in the server's OnDeserialize, which is why we named it "SyncDirection" instead of "ClientAuthority".

 

SyncDirection reimplemented.
https://github.com/vis2k/Mirror/pull/3244

Now properly broadcasts ClientToServer components to other clients too
Also added a demo in Examples/SyncDirection.

 

Preparing the upgrade path to NetworkTransform V3.
Trying to be very careful so nothing breaks in your projects.

• NetworkTransformChild will be obsolete. use NT with public .target instead
• .clientAuthority will be obsolete. set SyncDirection to ClientToServer instead.

Note that everything still works even if you ignore the warnings.
But eventually the old stuff will be removed

 

I update Mirror 2022.9.15 and found Error

Assets\Mirror\Runtime\NetworkReaderExtensions.cs(156,17): error CS0246: The type or namespace name 'ReadOnlySpan<>' could not be found (are you missing a using directive or an assembly reference?)

Assets\Mirror\Runtime\NetworkWriterExtensions.cs(188,37): error CS0246: The type or namespace name 'Span<>' could not be found (are you missing a using directive or an assembly reference?)

Assets\Mirror\Runtime\NetworkWriterExtensions.cs(188,19): error CS1061: 'Guid' does not contain a definition for 'TryWriteBytes' and no accessible extension method 'TryWriteBytes' accepting a first argument of type 'Guid' could be found (are you missing a using directive or an assembly reference?)

My current Unity Editor 2020.3.26f1

 

I succeed to make the playerclient connected when the scene change. Now, the player prefab for my client is in host view but not in the corresponding client view. Do someone can tell me why ?

 

Please try latest Mirror from Github. We added 2019 support again last week or so.