Streaming custom assets in FiveM without wrecking performance

Any file placed in a resource's `stream` folder is registered with the game's asset system and can override or extend GTA V's own content. The game does not care which resource a file came from — it builds one flat namespace keyed by asset name. That single fact explains most streaming bugs.

fx_version 'cerulean'
game 'gta5'

-- everything under stream/ is picked up recursively
files { 'data/vehicles.meta', 'data/carvariations.meta' }

data_file 'VEHICLE_METADATA_FILE'   'data/vehicles.meta'
data_file 'VEHICLE_VARIATION_FILE'  'data/carvariations.meta'
data_file 'HANDLING_FILE'           'data/handling.meta'

Because asset names are global, two resources shipping a prop called `prop_bench_01b` will fight. Whichever loads last wins, and the other MLO now has a bench from a different building — or no bench at all. Symptoms are geometry that flickers, textures that are wrong in one interior only, or props that vanish after a restart because load order changed.

find resources -path '*/stream/*' -type f -printf '%f\n' \
  | sort | uniq -d

• Any name in that output is a conflict you have right now.
• Fix it by renaming inside the resource that is least referenced elsewhere — and update its ymap/ytyp accordingly.
• Prefix your own custom assets with something unique to your server so you never collide with a purchased pack.

Add-on cars are the most common streamed content and the most common source of client memory problems. Each one carries a model, a texture dictionary and metadata, and it occupies memory whether or not anybody drives it.

1. 1Put the yft and ytd files in stream/, and the vehicles.meta, carvariations.meta and handling.meta in a data/ folder declared with data_file.
2. 2Make sure the spawn name is unique across every vehicle pack you run. Duplicate spawn names silently break carvariations.
3. 3Check the texture sizes. A 4096×4096 dictionary for one car is common in free packs and completely unnecessary — 2048 is plenty, 1024 for detail maps.
4. 4Verify handling.meta exists and is referenced. A missing handling entry produces a car that drives like a brick and reports no errors.
5. 5Test with an empty server first. If a vehicle crashes you alone, it will crash everyone.

An MLO replaces or adds an interior. Beyond the geometry, it brings ytyp archetypes, ymap placements, interior room definitions and often a navmesh. Installing one is more than dropping a folder in.

• If the MLO replaces a vanilla interior, it usually needs an IPL disabled or enabled from a client script. The readme will say so; people skip it and then report "the old walls are still there".
• Occlusion matters. A large interior without proper occlusion tanks frame rate because the engine draws the whole thing from outside.
• Check the collision. Free MLOs frequently ship broken collision on one floor, which players find within an hour.
• Navmesh affects NPCs and, in some frameworks, pathing for jobs. A missing ynv means peds walk through walls.

CreateThread(function()
  -- remove the vanilla shell
  RemoveIpl('post_hw1_10_producers')
  -- and load the replacement
  RequestIpl('my_custom_interior')
end)

GTA V allocates fixed-size pools for objects, entities, vehicles and more. Heavy custom content exhausts them, and the client crashes with a pool-related message. FiveM lets you raise specific pools — but raising everything "to be safe" costs memory and can itself cause instability.

// in your resource's fxmanifest, or via a dedicated resource
{
  "sv_poolSizesIncrease": {
    "TxdStore": 50000,
    "Object": 2000
  }
}

1. 1Reproduce the crash and read the exact pool name from the client log or crash dialog.
2. 2Raise that one pool by a modest amount.
3. 3Test again. If it moves to a different pool, you are treating a symptom — you probably have too much content.
4. 4If crashes persist, bisect your streamed resources the same way you would bisect a performance problem.

GTA V ships in versioned builds, and DLC content is only available on the build that introduced it. `sv_enforceGameBuild` pins which one your server runs. Change it and assets built for another build stop resolving — textures go white, vehicles fail to spawn, clothing components disappear.

• Pick the build your content requires, write it down, and treat it as part of your server's identity.
• When buying an MLO or a vehicle pack, check which build it targets before you install it.
• Changing the build is a planned migration, not a config tweak. Test on a copy of the server first.

The numbers are guidance, not law — a server with 6 GB of well-optimised content can behave better than one with 2 GB of badly compressed textures. What matters is that somebody is watching the total and the per-asset quality, rather than adding whatever looks nice this week.