Knowledge Base: Profiling on Device with Unreal Insights

Article written by Ryan B.
Unreal Insights helps developers identify bottlenecks, which is useful when optimizing for performance. At a high level, Unreal Insights is a stand-alone profiling system that integrates with …

https://dev.epicgames.com/community/learning/knowledge-base/WjEy/unreal-engine-profiling-on-device-with-unreal-insights

Thanks for this! I’ve been enjoying the tool for personal testing, but I have some questions when it comes to using Unreal Insights remotely.

It has been my experience so far that: 1) Unreal Insights must be opened before an instance of the project is launched in order to connect. 2) Stopping tracing using Trace.Stop and then starting again has the effect of thereafter only storing trace data on the local machine, while no longer sending any data to the viewer application on my machine.

It would be nice to be able to stop/start tracing either from within the game instance or from the viewer application while still maintaining the link between the two. It’s not the end of the world though, as I can take the normal approach of embedding the tracing commands as command line arguments, and then essentially tracing continuously throughout the game from the beginning.

This is where my questions come in. Because the trace files get very large very fast, I am wondering the following: 1) If there is a live connection between the game and viewer app, is any trace data being stored on the game’s local computer (even in a temp directory)? 2) What do I need to move around on my end, in order to not be writing potentially up to 100GB of data to my C drive SSD in one session? For example, is there a temp folder where the data will be stored temporarily as it’s coming into my viewer app that I can move/redirect to another drive, and/or can I move the Unreal Insights application itself to my other drive?

TLDR
I want to ensure that the minimum amount of trace data gets written onto the computer of someone who is sending that data to me while testing, and also minimize the amount of that data that gets written to my C drive. If that means moving all of Unreal Engine to the D drive, that shouldn’t be too much of an issue.

Sorry for rambling, thanks so much!

Best,

Lorenzo