SmoothServer
Networking and performance tuning for Valheim dedicated servers: send cadence, adaptive per-peer budgets, async save, telemetry. Optional client half adds zstd compression and a shared map.
About this mod Author’s original text
SmoothServer
Actively maintained for Valheim 1.0. Rebuilt for 1.0.7 on launch day and kept current as patches land;
version 1.x of the mod is in the works. Bugs and ideas: GitHub issues.
Designed and thought up by Nosferatu from real pain points hit running a co-op server.
Coded using Claude, tested by humans.
Networking and performance tuning for Valheim dedicated servers — and, since 0.3.0, an optional
client half in the same DLL.
The server half is the point of the mod and it still needs zero client installs:
[General] EnforceClientMod defaults to false, so vanilla players can always join. Install the
same package on players' machines as well and you additionally get packet compression, a client
send budget and a server-wide shared map.
Installing
Server admins — install into the server's profile
(BepInEx/plugins/SmoothServer). Everything under "Server modules" below starts working
immediately; nobody has to install anything. Config file: Nosferatu.SmoothServer.cfg in the
server's BepInEx/config.
Players — install into your own profile only if the server also runs SmoothServer 0.3.0+.
[General] Mode is Auto: a dedicated server runs the server half, your game runs the client
half. You get compression, the client send budget and the shared map; server-owned settings are
pushed to you by the server.
The package contains six DLLs, not one: SmoothServer.dll plus ZstdSharp.dll,
System.Memory.dll, System.Buffers.dll, System.Numerics.Vectors.dll and
System.Runtime.CompilerServices.Unsafe.dll (the zstd codec and its dependencies — none ship
with Valheim or BepInEx). A mod manager handles this; hand-installers must copy all six.
Mods this replaces — uninstall them first
| Uninstall | Replaced by | Where |
| --- | --- | --- |
| CW_Jesse / BetterNetworking | Compression + SteamRates + SendQueueGuard | server and clients |
| Mydayyy / ServerSideMap | SharedMap | server and clients |
Both must go from every machine. If BetterNetworking is still installed, Compression refuses
to patch (FAILED(...) in the module summary) and the rest of SmoothServer loads normally — it
will not break your server, it just will not compress. SharedMap imports an existing.mod.serversidemap.explored file once on first start, so no exploration is lost.
Server modules
Each module has its own Enabled toggle in its config section.
- Telemetry [Telemetry] — periodic fps / frame-time / ZDO-rate log line. No gameplay effect.
- FrameRate [FrameRate] — raises the dedicated server's Unity frame cap. 60 is a good
default on modern hardware: roughly +4pp of one CPU core for half the tick latency.
- SendCadence [SendCadence] — sends ZDO updates to every peer on a fixed interval
(SendHz, default 20) instead of vanilla's one-peer-per-frame round robin. Scales with player count.
- SendBudget [SendBudget] — the ZDO send-queue high-water mark and minimum chunk size,
exposed as config: HighWaterBytes defaults to 65536 (vanilla 10240), MinChunkBytes to 2048
(same as vanilla). Acts as the fallback when AdaptiveBudget is off.
- CreateBudget [CreateBudget] — objects created per frame, exposed as config (default
matches vanilla, i.e. a no-op until raised).
- PeerTelemetry [PeerTelemetry] — per-peer ping, throughput and Steam send-queue sampling.
No patches; feeds AdaptiveBudget.
- AdaptiveBudget [AdaptiveBudget] — a per-peer send budget from each peer's measured
bandwidth-delay product, clamped, EMA-smoothed, and backed off while Steam's pending byte count
says the pipe is congested. A player on fibre next door and one on satellite no longer share
one number.
- SteamRates [SteamRates] — raises Steam's SendRateMax (default 1 MB/s).
SendRateMin stays at vanilla on purpose: it is a floor on Steam's own bandwidth estimate,
and raising it stops the congestion controller backing off for weak connections.
- SendQueueGuard [SendQueueGuard] — defers, never drops, while a peer's Steam send queue is
backed up, and survives the Steamworks throws that can occur mid-handsha
Install & use Install: BepInEx plugin
- The archive from playbuff is the mod itself — usually a BepInEx plugin (a .dll or a plugin folder once unzipped).
- Recommended: use a community mod manager (such as r2modman) — pick this game, import the mod, and the manager sets up BepInEx and its dependencies for you.
- Manual route: install the BepInEx loader in the game folder, then drop the unzipped .dll or plugin folder into BepInEx/plugins/.
- Launch the game — the BepInEx console logs every plugin it loads; seeing this mod in the log means it is installed.
Mods with listed dependencies need those installed too, or they will not load. Options are usually changed in-game or in the plugin's config file. In multiplayer, the host and every client need the same mods installed.
Install these first, or the mod will not work: