FiveM Lua Optimization Guide 2026: Write Faster Scripts for RP Servers

Poorly optimized Lua scripts are the number one cause of FiveM server lag. Here are the most impactful optimizations.

1. Avoid Per-Tick Loops

The most common mistake:

-- BAD: Runs every frame (~60 times per second)
Citizen.CreateThread(function()
    while true do
        Wait(0)
        -- Heavy operation every frame
        local coords = GetEntityCoords(PlayerPedId())
        DrawMarker(...)
    end
end)

-- GOOD: Only run heavy operations occasionally
Citizen.CreateThread(function()
    while true do
        Wait(1000) -- Once per second
        local coords = GetEntityCoords(PlayerPedId())
        -- Check distance, then switch to fast loop only when needed
        if #(coords - targetCoords) < 50.0 then
            nearTarget = true
        else
            nearTarget = false
        end
    end
end)

Citizen.CreateThread(function()
    while true do
        if nearTarget then
            Wait(0)
            DrawMarker(...)
        else
            Wait(500)
        end
    end
end)

2. Cache Natives

-- BAD: Calling expensive natives repeatedly
Citizen.CreateThread(function()
    while true do
        Wait(0)
        local ped = PlayerPedId()  -- Called every frame
        local coords = GetEntityCoords(ped)  -- Called every frame
    end
end)

-- GOOD: Cache values
local cachedPed = PlayerPedId()
local cachedCoords = GetEntityCoords(cachedPed)

Citizen.CreateThread(function()
    while true do
        Wait(500)
        cachedPed = PlayerPedId()
        cachedCoords = GetEntityCoords(cachedPed)
    end
end)

3. Minimize Database Calls

-- BAD: Database query on every event
RegisterNetEvent('myResource:getData')
AddEventHandler('myResource:getData', function()
    MySQL.query('SELECT * FROM players WHERE id = ?', {source}, function(result)
        -- ...
    end)
end)

-- GOOD: Cache database results
local playerCache = {}

AddEventHandler('playerConnecting', function()
    local src = source
    MySQL.query('SELECT * FROM players WHERE id = ?', {src}, function(result)
        playerCache[src] = result[1]
    end)
end)

4. Use Resmon to Find Lag

Type resmon 1 in the server console. Any resource consistently above 1ms should be investigated.

5. Avoid table.insert in Hot Loops

-- BAD: table.insert is slow in tight loops
for i = 1, 10000 do
    table.insert(myTable, value)
end

-- GOOD: Direct index assignment
for i = 1, 10000 do
    myTable[#myTable + 1] = value
end

FAQ

What causes FiveM server lag? Most commonly: Lua scripts running expensive operations every frame (Wait(0) loops).

How do I find which script is lagging? Use resmon 1 in the server console.

Does the number of resources affect performance? Yes. Fewer, well-optimized resources perform better than many small, unoptimized ones.

Related: FiveM resmon guide, FiveM event security, ox_lib tutorial