Defold includes a set of profiling tools that are integrated with the engine and the build pipeline. These are designed to help find problems with performance and memory usage. The built-in profilers are available on debug builds only.

The runtime visual profiler

Debug builds feature a runtime visual profiler that displays live information rendered overlayed on top of the running application:

function on_reload(self)
    -- Toggle the visual profiler on hot reload.

Visual profiler

The visual profiler provides a number of different function that can be used to change the way the visual profiler presents its data:


Refer to a the profiler API reference for more information about the profiler functions.

The web profiler

While running a debug build of the game, an interactive web-based profiler can be accessed through a browser. It allows you to sample your game over a series of frames and then analyze each frame in detail.

To access the profiler:

  1. Start your game on your target device.
  2. Select Debug ▸ Open Web Profiler menu. Alternatively, for example, when you use multiple targets simultaneously, you can open a web browser and point it to http://<device IP>:8002 where <device IP> is the IP address of the device. You can find the IP numbers of your target devices in the Project ▸ Target menu. If you are running your game on your desktop computer, http://localhost:8002 will bring up the profiler.

Web profiler mode At the top, next to the Capture button there are radio buttons to switch between the CPU/Frame profiler and the Resource profiler.

CPU/Frame profiler

The CPU profiler is divided into 4 sections that all give different views into the current sample data. To update the sample data, press the Capture button at the top.

Web profiler

Frames overview
The frames overview plots the currently sampled 20 frames side by side. The height of each bar shows the time spent in the frame. The number on the left hand side shows the max time spent in a frame in the current sample data.

Frames overview

Below the frames overview is a detailed frame data view.

Click on a frame bar in the overview to show the data for that specific frame in the data view.

Frame data
The frame data view is a table where all data for the currently selected frame is broken down into detail. You can view how many milliseconds are spent in each engine scope (to the left) and also see sample points within the scopes (middle column). On the right hand side is a table of counters. They make it is easy to, for instance, track the number of draw calls required for each frame in the sample data.

Frame data

Ticking the checkbox associated with a sample point or counter adds that data to the plot below.

Frames plot
The frames plot view displays a plot over all sampled frames with the data you have selected in the frame data table above the plot. The plot shows frame number on the X axis and time (in milliseconds) or counts on the Y axis. Each selected data point is drawn in the color specified in the frame data table.

Frames plot

Frame time chart
The frame time chart breaks the frame down visually making it easy to inspect where the engine spends its time during the selected frame.

Frame timechart

Resource profiler

The resource profiler is divided into 2 sections, one showing a hierarchical view of the collections, game objects and components currently instantiated in your game, and the other showing all currently loaded resources.

Resource profiler

Collection view
The collection view shows hierarchical list of all game objects and components currently instantiated in the game and from which collection they originate. This is a very useful tool when you need to dig into and understand what you have instanced in your game at any given time and from where the objects originate.
Resources view
The resources view shows all resources currently loaded into memory, their size and the number of references to each resource. This is useful when optimizing memory usage in your application when you need to understand what is loaded into memory at any given time.

Build reports

When bundling your game there is an option to create a build report. This is very useful to get a grip on the size of all the assets that are part of your game bundle. Simply check the Generate build report checkbox when bundling the game.

build report

The builder will produce a file called “report.html” alongside the game bundle. Open the file in a web browser to inspect the report:

build report

The Overview gives an over all visual breakdown of the project size based on resource type.

Resources shows a detailed list of resources that you can sort based on size, compression ratio, encryption, type and directory name. Use the “search” field to filter the resource entries displayed.

The Structure section shows sizes based on how resources are organized in the project file structure. Entries are color coded from green (light) to blue (heavy) according to the relative size of the file and directory content.

External tools

In addition to the built-in tools, there is a wide range of free high quality tracing and profiling tools available. Here is a selection:

ProFi (Lua)
We do not ship any built-in Lua profiler but there are external libraries that are easy enough to use. To find where your scripts spend time, either insert time measures in your code yourself, or use a Lua profiling library like ProFi.

Note that pure Lua profilers add quite a lot of overhead with each hook they install. For this reason you should be a bit wary of the timing profiles you get from such a tool. Counting profiles are accurate enough though.

Instruments (macOS and iOS)
This is a performance analyzer and visualizer that is part of Xcode. It allows you to trace and inspect the behavior of one or more apps or processes, examine device specific features (like Wi-Fi and Bluetooth) and much more.


OpenGL profiler (macOS)
Part of the package “Additional Tools for Xcode” that you can download from Apple (select Xcode ▸ Open Developer Tool ▸ More Developer Tools... in the Xcode menu).

This tool allows you to inspect a running Defold application and see how it uses OpenGL. It allows you to do traces of OpenGL function calls, set breakpoints on OpenGL functions, investigate application resources (textures, programs, shaders etc), look at buffer contents, and check other aspects of the OpenGL state.

opengl profiler

Android Profiler (Android)

A set of profiling tools that captures realtime data of your game’s CPU, memory, and network activity. You can perform sample-based method tracing of code execution, capture heap dumps, view memory allocations, and inspect the details of network-transmitted files. Using the tool requires that you set android:debuggable="true" in “AndroidManifest.xml”.

android profiler

Note: Since Android Studio 4.1 it is also possible to run the profiling tools without starting Android Studio.

Graphics API Debugger (Android)

This is a collection of tools that allows you to inspect, tweak and replay calls from an application to a graphics driver. To use the tool requires that you set android:debuggable="true" in “AndroidManifest.xml”.

graphics api debugger