LoadTimeProfiler

Profiles mod loading times during game startup, world loading, and dedicated server boot. Creates clear per-mod reports and keeps the latest 10 runs for easy comparison.

It starts before normal BepInEx plugins and writes an easy-to-read timing report for each launch. It does not change gameplay, items, worlds, or server settings.

Features

• Measures client startup from launch to the main menu.
• Measures the trip from the lobby to a playable world.
• Measures dedicated server startup until the server is ready.
• Shows how much time individual mods spend during plugin setup, including construction, Awake, OnEnable, and Start.
• Shows per-mod synchronous work during the important ZNetScene.Awake and ObjectDB.Awake loading stages.
• Records a timeline of major Valheim loading stages, making long pauses easier to spot.
• Keeps the latest 10 reports so you can compare runs before and after changing your mod list.
• Works on clients and dedicated servers without DataForge or ServerSync.

Manual Installation

Place LoadTimeProfiler.dll directly inside:

BepInEx/patchers

Do not place it in BepInEx/plugins. A patcher needs to start before regular plugins so it can measure their loading time.

Install it separately on every client or dedicated server that you want to profile. A server installation measures the server; a client installation measures that client.

How To Use

1. Start Valheim or your dedicated server normally.
2. On a client, wait for the main menu and then enter a world if you also want a lobby-to-world report.
3. On a dedicated server, wait until world loading is complete and the server is ready for connections.
4. Open the newest report in:

BepInEx/config/LoadTimeProfiler

Each report is named with its launch date and time. Up to 10 reports are stored in this folder. When an 11th report is created, the oldest report is removed automatically.

Compare several runs before deciding that one mod is slow. Loading time can change because of disk cache, network conditions, world size, and other programs running on the computer.

Dedicated Server Behavior

Install the same LoadTimeProfiler.dll in the dedicated server's own BepInEx/patchers folder. No client installation is required to measure the server itself.

When the valheim_server process starts, LoadTimeProfiler automatically switches to dedicated server mode and creates a Server Startup report. It measures:

• BepInEx startup and plugin construction, Awake, OnEnable, and Start work.
• Major server loading stages such as ZNetScene.Awake, ObjectDB.Awake, ZoneSystem.Start, and DungeonDB.Start.
• Synchronous per-mod Harmony callback time during ZNetScene.Awake and ObjectDB.Awake.
• Startup through world and location generation until Valheim opens the server for connections.

The report is saved on the server machine at:

BepInEx/config/LoadTimeProfiler

Server reports are not sent to connected players. Installing LoadTimeProfiler only on a client measures that client, while installing it only on the dedicated server measures the server. The server also keeps only its newest 10 reports.

Reading The Report

• Plugin construction/Awake/OnEnable shows time spent while BepInEx creates and enables each plugin.
• Plugin Start shows measured work from plugin Start methods.
• Timeline shows the order and duration of major Valheim loading stages.
• Scoped deep attribution shows synchronous Harmony callback time assigned to mods during ZNetScene.Awake and ObjectDB.Awake.
• Unattributed time is work that cannot be safely assigned to one mod.

The slowest entries are useful investigation targets. They are not automatic proof that a mod is broken; manager mods such as Jotunn may perform work on behalf of several other mods.

Example Report

The numbers below are only an example. Your results will depend on your computer, world, server, and installed mods.

Start To Lobby

=== Start To Lobby ===
Result: completed
Total: 2 min 15.781 s
Milestone intervals:
  Breakdown: lifecycle execution + remaining time until the next milestone.
  0.714 s: LoadTimeProfiler.Patcher.Finish
  0.106 s: LoadTimeProfiler.Patcher initialized
  82.336 s: BepInEx.Chainloader.Start
  32.418 s: BepInEx.Chainloader.Start complete
  16.894 s (16.463 s + 0.431 s): FejdStartup.Awake
  0.000 s: FejdStartup.Start
  0.244 s (0.244 s + 0.000 s): FejdStartup.SetupGui
  3.068 s (2.771 s + 0.297 s): FejdStartup.SetupObjectDB
BepInEx startup:
  Before Chainloader.Start (includes Chainloader.Initialize): 820.046 ms
  Chainloader.Start: 1 min 22.336 s
Plugin construction/Awake/OnEnable:
  6.534 s: MonsterLabZ
  4.629 s: MonstrumDeepNorth
  4.091 s: WarfareFireAndIce
  3.134 s: SouthsilArmor
  2.965 s: Jewelcrafting
  2.770 s: CrystalLights
  2.486 s: Warfare
  2.367 s: ValheimCuisine

This section helps you find mods that spend a long time being created or enabled before the main menu appears.

Lobby To World

=== Lobby To World ===
Result: completed
Total: 52.154 s
Milestone intervals:
  Breakdown: lifecycle execution + remaining time until the next milestone.
  0.022 s (0.001 s + 0.021 s): FejdStartup.OnWorldStart
  1.468 s (0.000 s + 1.468 s): FejdStartup.TransitionToMainScene
  0.233 s (0.000 s + 0.233 s): FejdStartup.LoadMainScene
  0.043 s (0.043 s + 0.000 s): Game.Awake
  0.009 s (0.008 s + 0.001 s): ZoneSystem.Awake
  2.262 s (2.261 s + 0.001 s): ZNet.Awake
  15.022 s (13.311 s + 1.711 s): ZNetScene.Awake
  8.769 s (7.079 s + 1.690 s): ObjectDB.Awake
  0.033 s (0.032 s + 0.001 s): Game.Start
  0.438 s (0.437 s + 0.001 s): ZoneSystem.Start
  3.387 s (3.387 s + 0.000 s): DungeonDB.Start
  4.285 s (0.293 s + 3.992 s): ZNet.Start
  16.010 s (0.301 s + 15.709 s): Game.RequestRespawn
  0.167 s (0.167 s + 0.000 s): Game.SpawnPlayer
Measured lifecycle execution times (prefix -> finalizer, inclusive):
  13.311 s: ZNetScene.Awake
  7.079 s: ObjectDB.Awake
  3.388 s: DungeonDB.Start
  2.262 s: ZNet.Awake
  0.437 s: ZoneSystem.Start
  0.301 s: Game.RequestRespawn
  0.293 s: ZNet.Start
  0.167 s: Game.SpawnPlayer
Scoped deep lobby attribution:
  Exclusive synchronous Harmony callback time in ObjectDB.Awake and ZNetScene.Awake.
  Breakdown order: ObjectDB + ZNetScene.
  Prepared callbacks: installed=4, existing=398, skipped=2, failed=0, setup=0.021 s
  11.973 s (0.189 s + 11.783 s): Jotunn
  4.423 s (4.418 s + 0.005 s): DataForge
  0.813 s (0.813 s + 0.000 s): AdminQoL
  0.534 s (0.047 s + 0.486 s): EpicMMOSystem
  0.246 s (0.211 s + 0.035 s): WarfareFireAndIce
  0.180 s (0.116 s + 0.064 s): Jewelcrafting

For a milestone such as 15.022 s (13.311 s + 1.711 s): ZNetScene.Awake, the first value inside the parentheses is measured execution time. The second is the remaining time before the next milestone.

The scoped attribution rows use ObjectDB + ZNetScene order. For example, DataForge used 4.418 s during ObjectDB.Awake and 0.005 s during ZNetScene.Awake in this sample.

Measurement Limits

LoadTimeProfiler safely assigns synchronous work that it can observe. Network waits, coroutine continuations, background work, vanilla work, transpiled code, and work completed before the patcher starts may remain unattributed. Work delegated through another framework may be listed under that framework instead of the mod that requested it.

Changelog

1.0.0

• Initial public release of LoadTimeProfiler.
• Supports client loading and dedicated server startup profiling.