FiveM Resmon Explained: How to Find and Fix High-ms Scripts

When a FiveM server "feels laggy", the cause is usually one or two scripts eating CPU time on every frame. FiveM has a built-in tool to find them: resmon, the resource monitor.

Open resmon

Press F8 in-game and type:

resmon 1

A table appears in the corner with every running client resource. Type resmon 0 to hide it.

Read the columns

At 60 FPS a whole frame is about 16.6 ms, and the game itself needs most of it. Every millisecond a script takes comes straight out of the player's FPS.

What is a good value?

Values while a menu is open or a job is running can be higher. What matters is what a script costs when nobody is using it, because players spend most of their time there.

The usual culprits and how to fix them

Loops that never sleep

The most common problem: a loop that runs every frame to check a distance.

CreateThread(function()
    while true do
        Wait(0)
        local coords = GetEntityCoords(PlayerPedId())
        if #(coords - shopCoords) < 2.0 then
            DrawText3D(shopCoords, "[E] Open shop")
        end
    end
end)

Fix it by sleeping long when the player is far away and only running every frame when they are close:

CreateThread(function()
    while true do
        local sleep = 1000
        local coords = GetEntityCoords(PlayerPedId())
        local distance = #(coords - shopCoords)
        if distance < 20.0 then
            sleep = 0
            if distance < 2.0 then
                DrawText3D(shopCoords, "[E] Open shop")
            end
        end
        Wait(sleep)
    end
end)

Doing the work yourself instead of using zones

If you use ox_lib, lib.points and lib.zones handle the distance checks for you and only call your code when the player is nearby. A script built on them idles at 0.00 ms.

local point = lib.points.new({ coords = shopCoords, distance = 2.0 })

function point:onEnter()
    lib.showTextUI("[E] Open shop")
end

function point:onExit()
    lib.hideTextUI()
end

Markers drawn for every location at once

Drawing 50 markers per frame for 50 garages costs a lot. Draw only those within 20-30 metres, or replace markers with ox_target interactions.

Native calls repeated every frame

Calls like PlayerPedId() and GetVehiclePedIsIn() are cheap alone, but add up across many scripts. ox_lib's cache.ped and cache.vehicle keep them for you.

Go deeper with the profiler

For a precise picture, record a profile in F8:

profiler record 300
profiler view

This records 300 frames and opens a timeline showing which function in which resource took the time.

Server-side lag

resmon only shows the client. If the server console shows hitch warnings like server thread hitch warning, the problem is on the server: slow database queries, big loops over all players, or a script waiting on an HTTP request. Run the same profiler commands in the server console to find it.

Scripts that start light

SleepyCode scripts are built to idle at or near 0.00 ms, and the documentation lists the measured values, for example for Garages V2. Browse the FiveM scripts, or read how to install FiveM scripts properly.