[Bug Report] Not building scene

And then came the patch 4.7.4 and nothing has changed. How to hang a computer building project from the scene, and hangs up.
When it repaired? Problems occur on different PC. And I even monitors community questions. This happens not only weak, but also on strong PC!
Why does no one want to solve this serious problem?

Hi Othelnic12 -

We want to address an issues that users report, but I am going to need some more information from you you regarding exactly what you are experiencing.

When you say Building Scene, are your referring to building lighting and geometry for the scene or packaging and launching the game itself? Are you getting a specific message from the editor? A screenshot here would be helpful. It seems you are also seeing a bug reported in other locations, can you link those here for me. I can then get together with the support people working on those issues and compare notes.

Thank You

Eric Ketchum

I’m talking about Building lighting. I apologize for the inaccuracy.
Problems arise regardless of what stage and that it finds. Screenshot I just can not do! Since I do not have any control after hovering.
But of course, and many others.
However, all bug reports are reduced to one account, “Get more RAM.” That’s just it happens on computers with 12GB of RAM, and 32GB. And the answer to all one. Why Are? Is not clear.
It would be desirable to these people, and myself included, have already heard!
We understand that in 4.7, much has changed. But still.

Hi Othelnic12 -

Without more specifics which I would need to narrow down the exact cause, here is a complete Swarm Agent Troubleshooting Guide for Light Build Problems:

Why do I get the error ‘Lightmass Crashed’ when I build lighting?

There can be a lot of reasons but most of them (99.9%) boil down to hardware and resource related issues.

Where to Start:

1 - Hardware Limitations

  • RAM - When lightmass runs out of RAM it will use the virtual cache setup by your OS to write information to the hard drive. This will exponentially slow down light builds.

Recommendation: Upgrade RAM where possible or increase Virtual Cache for your OS

2 - Clean and Validate the Derived Data Cache:

  • Open Swarm Agent from the taskbar > Menu > Cache > Click Clean and Click Validate
  • Navigate to the following file path and delete all folders while the editor is closed: X: / Users / [Your Computer Name] / AppData / Local / UnrealEngine /

Note: This folder is a hidden system folder. Make sure to unhide system folders first to see it.

3 - Insure that the Hard Drive that Your Swarm Cache is set to use (see above folder) has a significant amount of free space, the larger the level you are attempting to build lighting for the more space you will ultimately need. (1GB+ lowest for large levels and 20GB+ for HUGE levels → at which point we actually recommend using Dynamic Lighting)

Other Possible Causes not directly associated with Hardware and Resource Limitations (the other 0.1%):

1 - Check to insure that you are not running two instances of the Swarm Agent (it is a little yellow and black “S” in the taskbar of windows)

2 - Turn off any anti-virus or firewall software temporarily and see if that eliminates the Building errors, if so then add an exception for Swarm Agent to your Firewall Software

3 - Computers should not use Non-Latin Characters, only A to Z without accent or Umlaut and 0 to 9 are permitted, in their Names, User Names, or the Folder Structure and insure that the first character of a folder or user name is not a number.

Fringe Cases of Issues (not reported since 4.2):

1 - Install / Re-install Visual C++ Redistributes

2 - Re-install / Update (.)NET Framework from Microsoft

3 - Re-install Windows OS

Thank You

Eric Ketchum

It’s all written and boys Russian community, and it does not solve the problem completely!

Hi Othelnic12 -

I think we may be having a language problem. Can you carefully recap your problem in your native language?

Thank You

Eric Ketchum

Попробуем…
При попытке билдинга освещения, происходит зависание пк.
Я не имею никакого контроля над движком и системой в это время. И не получаю никаких ошибок.
Во время передачи информации о билдинге, я успеваю открыть Swarm agent и смотреть лог вплоть до зависания. И там опять же нету не единой ошибки.

Сегодня я переустановил полностью систему. И попробовал вновь. И снова зависание билдинга.
Я уверен что это никак не зависит от оперативной памяти или видео карте. Поскольку даже на более плохих пк, знаю людей у которых все отлично работает.

Напомню, что проблема началась в версии 4.7.0 и продолжается по сей патч 4.7.5. И причина проблемы неизвестна, она случайна…
В версии 4.6 таковых проблем не было.

Hey Othelnic12 -

Ok I think I know how we might be able to begin to track this issue down.

Open Swarm Agent (outside of the engine, it is located at …\Engine\Binaries\DotNET\SwarmAgent.exe)

In the Settings Tab, Change the Verbosity setting to Verbose

Open the engine in 4.7 and try to build lighting.

Next back in Swarm Agent copy the information in the Log tab to a Text Document and upload here. (It will be quite long, but that’s ok, a CTRL-A should select all)

Thank You -

Eric Ketchum

Made as indicated. However, my PC freezes well. And the log information, is not able to provide.

There was a single file. I think this is it.

Hi Othelnic12 -

Look in the location listed in your Swarm Agent as your Cache Folder and see if you can find a sub directory called logs, and a text log file that matches the date of your failed light build?

Thank You

Eric Ketchum

Hi Othelnic12 -

We are looking into the logs now, but can I ask when your CPU freezes are you stopping it or does it crash and restart itself? If you are stopping it can you let it run for as long as possible to one see if it self-recovers and two see if we can get more information from the new log file.

Thank You

Eric Ketchum

Restarts the computer manually. Above the control system hangs no idea.
Already tried to wait, after half an hour, no results.

Are you getting this behavior with a custom project? Can you try to build lighting on the First Person Template project?

Thank You

Eric Ketchum

On any project

Hi Othelnic12 -

Thank you for the additional information regarding the error continuing in version 4.8 Master Branch. We are working to narrow down your issue specifically now. To further help us out can you follow these steps to test the Swarm Agent and Engine and post your Agent Logs and your Project (which can be found in the Project’s Saved Folder):

  1. Open First Person Template Project in 4.7.6 (Launcher) with NO Starter Content
  2. Select the Directional Light and Change its Mobility to Static from Stationary
  3. Build Lighting
  4. You’ve reported that the computer freezes at around 87%, once you feel that the computer has frozen, wait a total of 3 Hours before attempting to restart your PC or Close the Editor (The Time is important, please do not rush it.)
  5. Assuming the light did not finish building and you had to restart the CPU, take the Project Directory (minus the Intermediate Sub-Folder) and Zip it up and attach it here (This will include your Project Log Files) and attach you Swarm Agent Log files as well.
  6. If you had to restart you CPU, Open Windows Event Viewer
  7. In Windows Event Viewer, Find and Select the Error or Critical Event that corresponds with the Restarting of your computer’s timeframe (You can Select several if you are uncertain).
  8. In Windows Event Viewer once the Events are selected you can export them on the right hand menu. IMPORTANT NOTE: Please make sure that you export them with English language support (this will be an option on saving the Events)
  9. Once saved, you can then zip that file up and again attach it here.

Thank You for your assistance in tracking down this issue.

Eric Ketchum

The first successful news. This time Building was successful. I tried it, not only with a stationary light source, but also static. All builds, although it goes on for more than 30 minutes.

Hi Othelnic12 -

Can you now try to build lighting on the project you were originally using instead of First Person Template? Remember and this is important if First Person Template with One Light took 30 mins on your CPU, scale that timeframe upwards for your project based on its size. Also it might be helpful to change your Swarm Cache directory to another much larger hard drive, this will not speed the build up, but it will insure that you do not run out of cache memory (hard drive space) during the build. Large levels on production quality with everything being lit can take a significant amount of HDD space. (For Instance, a colleague and I built lighting for a moderate scene and while building at production quality at it took close to 50GB of HDD space.)

Let me know -

Eric Ketchum

I’ve tried just on this template.
Hard disk space 400+ GB do not think that is the problem.
Now I can build quite stable coverage on First Person template.
But it takes as I have said more than 30 minutes.
But there is one thing that I noticed in the construction of lighting in 4.8
and I am sure that in 4.7 as well:
The first building lighting works perfectly, no freezes, and a 1-minute maximum.

Can you clarify what you mean with “The first building lighting works perfectly, no freezes, and a 1-minute maximum”? Is the second time you build lighting running for 30 mins? Are you doing anything with the lighting or level between light builds one and two?