Smootheim
Server-side networking, save and player-join optimizations for supported Valheim dedicated Steam servers.
About this mod Author’s original text
Smootheim 0.2.2
Server-side networking, save and player-join optimizations for Valheim dedicated
Steam servers. Clients need no mods.
Smootheim spreads outgoing replication work fairly across players, increases the
Steam send allowance and rate, reduces join sorting work, and serializes saves
incrementally. It also skips unused dedicated-server terrain rendering work and
defers asset collection within time and memory limits.
In our testing this mod is sufficient to:
- Enable enjoyable transcontinental play (>60ms RTT, players can reliably parry!)
- Eradicate most lag from saves
- Eradicate most lag from player joins
Requirements
- Dedicated Steam server: Valheim 1.0.16 / build 25527701, 1.0.15 / build 25390671 or
1.0.12 / build 25253791, network version 40.
- BepInExPack_Valheim 5.4.2350.
This supplies the tested BepInEx 5.4.23.5 and HarmonyX 2.9.0 combination.
- Native integration has been tested on Linux x86-64. Windows is unverified.
No client-side installation is needed. In this release, optimizations activate
only on dedicated servers using Steam transport (crossplay off).
Install
Back up the world before installing or updating.
With a -compatible manager, install Smootheim into the profile used
to launch your dedicated server. The manifest declares the BepInEx dependency.
For manual installation, install the required BepInEx pack first, then copy this
archive's BepInEx/plugins/Smootheim/ directory into the server's matching
directory. Keep all three DLLs together and remove any duplicate older Smootheim
installation. This public package contains only the mod; it supplies no loader
or configuration files. The separate Linux AMP bundle includes both.
Start with Steam transport (crossplay off). Confirm these entries in
BepInEx/LogOutput.log:
Loading [Smootheim 0.2.2]
preflight=passed
patches=installed
Smootheim active; activation=enabled transport=Steam
Loading the plugin alone does not establish activation.
Configuration
First launch creates BepInEx/config/pub.rag.smootheim.cfg. Stop the server
before editing; changes require restart. Existing settings are preserved.
| Section / setting | Default | Purpose |
| --- | --- | --- |
| Networking / Enabled | true | Enable optimizations after compatibility checks |
| Networking / SchedulerEnabled | true | Fair, budgeted peer scheduling |
| Networking / SchedulerBudgetMs | 1 | Soft work allowance per frame |
| Networking / SendWindowBytes | 32768 | Outstanding send allowance |
| Networking / SteamSendRateBytesPerSecond | 524288 | Per-connection Steam send rate |
| Networking / DirtySyncMode | Enabled | Candidate tracking; Off, Shadow or Enabled |
| Performance / JoinSortEnabled | true | Reduce join sorting work |
| Performance / SelectedSaveSnapshots | true | Snapshot selected save data |
| Performance / BudgetedSaves | true | Incremental capture; requires SelectedSaveSnapshots |
| Performance / SkipTerrainRenderMesh | true | Skip unused terrain visual mesh work |
| Performance / DeferAssetCollection | true | Defer collection within configured limits |
Disable or remove
Set Networking / Enabled = false and DirtySyncMode = Off, then restart for a
vanilla networking baseline. To remove the mod, stop the server and remove all
three DLLs from BepInEx/plugins/Smootheim.
When reporting a problem, include the game build, mod version, server platform,
configuration, other mods and share complete logs.
Developer diagnostics
These features are for development and maintainer-directed troubleshooting,
not intended for end users. Leave them at their defaults unless the maintainer
requests a diagnostic run. They are grouped under [Troubleshooting] at the end
of the config file, separately from networking and performance settings.
| Setting | Default | Purpose |
| --- | --- | --- |
| MetricsIntervalSeconds | 300 | Aggregate network metrics; 0 disables |
| DirtySyncIntervalSeconds | 300 | Dirty tracking summaries; 0 disables |
| ReceiveEnabled | false | Temporary
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: