Cook Failure Out of Memory

Summary

This is a new thread continuing off of a previous one by request of Epic Staff.
This issue started happening to my team as of 2 updates ago (37.30) prior to that specific patch we were able to load into and get project size readings on sessions just fine. But now cook error as follows is incredibly consistent despite the content in the island being relatively the same as it was before the issue:

Following up from the previous thread, it seems to be affecting larger islands with higher actor counts. Our island last reported 59% project size and 80k memory, but the actor count is roughly 40k. Sometimes the project loads in and cooks fine and there wont be any issues until the next patch (presumably because it has to recook for the new build. But sometimes, like right now, its impossible to get a reading)

It gets more strange when it DOES actually let us into a session pretty consistently, just fine, and even lets us playtest the map perfectly, but still does not update the project size and reports the same cook error despite the map presumably being cooked in order for the session to load and be played.

Our only workaround has been to create revisions of the project where we delete many actors until the session cooks, then revert back to the revision before they were deleted and let the server cook from there, to which the issue remains gone until the next patch is released as the server only cooks what has been changed and not the entire map from scratch.

I have provided images of the error, and an image of the rare cases it lets us into the session just fine but still lacks project size (something that was consistent with other users on the previous thread too)

Any insight to this would be helpful, especially since these larger maps still fit within project and memory limitations and are only held back by this strange inconsistency.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Project Size

Steps to Reproduce

Have an island with 20-40k actors (sometimes more but other things like materials and such may have a play in it as well but it mostly seems related to actor count.) and simply loading into edit sessions which results in cook errors until it miraculously works.

Expected Result

Usual wait times when loading into a session and getting proper project size readings.

Error: [errors.com.epicgames.cookplugin.cookfailureoutofmemory]

Observed Result

Loading into a session will most of the time result in an out of Memory Cook Error, sometimes even letting you into the session perfectly fine and even private codes, yet project size will not update in most cases or straight up refuse to let you in.

Sometimes switching platforms for the sessions, like Switch 2, actually lets you into the live sessions more consistently and once again, it plays and works fine, but project size remains in a “?cooker out of memory” state despite the cook seemingly succeeding for the session to even exist.

Platform(s)

PC, Switch 2, iOS, PS4, PS5

Upload an image


Update: Here are images from the process I use to get the cook working. By deleting a bunch of actors and loading into a session, the project size actually calculated, then reverting back to the full map prior to deleting and loading the session, the project size calculated without a hitch or an issue and now my development will resume as normal until the next patch when this inevitably happens again.

Workaround that I found is create an empty level, start the session in it and then switch to the correct level. Much better, because there is no need to revert to previous versions

@EDMIRE could I get your island code?

Also, this came from one of our engine programmers:

To help with this, one idea would be after cook you could query the peak memory stats.

Something like:
Cooker peak memory reached: 90%

With that sort of info, the user could try deleting a few things to see how it affects the peak usage.

FORT-986455 is ‘Closed’ as ‘Fixed’. The issue will be addressed in 38.00.