"Build Lighting" Hangs at 66%, never finishes

anonymous_user_d44607c0 · September 2, 2015, 3:34am

Whenever I run a build from the editor, it gets stuck on “Building lighting” at 66%. I’ve tested this with both a level with some stuff in it, an empty level, and a level with a sky sphere with the same results. If I create a new blank project and attempt to build on the default map, I get no issues. I’m on Windows 10 64 bit, and here’s the full log from Swarm:

8:27:51 PM: Starting up SwarmAgent ...
8:27:51 PM:  ... registering SwarmAgent with remoting service
8:27:51 PM:  ... registering SwarmAgent network channels
8:27:51 PM:  ... initializing SwarmAgent
8:27:51 PM:  ......... certificate check has failed
8:27:51 PM:  ...... initializing cache
8:27:51 PM:  ......... using cache folder 'C:/Users/Mitchell/AppData/Local/UnrealEngine/4.9/Saved/Swarm\SwarmCache'
8:27:51 PM:  ......... recreating SwarmAgent cache staging area
8:27:51 PM:  ...... initializing connection to SwarmCoordinator
8:27:51 PM:  ......... using SwarmCoordinator on RENDER-01
8:27:53 PM:  ......... SwarmCoordinator failed to be initialized
8:27:53 PM:  ...... initializing local performance monitoring subsystem
8:27:53 PM:  ... initialization successful, SwarmAgent now running
8:27:53 PM: [Interface:TryOpenConnection] Local connection established
8:27:53 PM: [Job] Accepted Job B7580191-4FC7BE65-88620BA8-3862DDCE
8:27:53 PM: [Job] Launched Job UnrealLightmass_2015-09-01_02-23-03_1325512-64bit.exe
8:27:53 PM: [Job]     PID is 5916
8:27:53 PM: [Job]     GUID is "B7580191-4FC7BE65-88620BA8-3862DDCE"
8:27:53 PM: LogLightmass:Display: Lightmass Win64 started on: DESKTOP-OBSDO8V. Command-line: B75801914FC7BE6588620BA83862DDCE
8:27:53 PM: Lightmass Win64 started on: DESKTOP-OBSDO8V. Command-line: B75801914FC7BE6588620BA83862DDCE
8:27:53 PM: LogLightmass:Display: Processing scene GUID: B75801914FC7BE6588620BA83862DDCE with 6 threads
8:27:53 PM: Processing scene GUID: B75801914FC7BE6588620BA83862DDCE with 6 threads
8:27:53 PM: Building static lighting...
8:27:53 PM: LogGenericPlatformMisc:Warning: Failed to determine engine directory: Defaulting to ../../../Engine/
8:27:53 PM: Failed to determine engine directory: Defaulting to ../../../Engine/
8:27:53 PM: [Job] Found a parent connection for PID 5916
8:27:53 PM: [Job]     6E76F3F3 -> 539B416C
8:27:53 PM: [Interface:TryOpenConnection] Local connection established
8:27:54 PM: Measured CPU frequency: 4.08 GHz
8:27:54 PM: FStaticLightingSystem started using GKDOPMaxTrisPerLeaf: 4
8:27:54 PM: Number of texture mappings: 1
8:27:54 PM: Number of fluid mappings:   0
8:27:54 PM: Number of landscape mappings:   0
8:27:54 PM: Number of BSP mappings:     0
8:27:54 PM: Number of static mesh instance mappings: 1
8:27:54 PM: Reserving memory for 1 meshes, 2208 vertices, 3968 triangles
8:27:54 PM: Scene surface area calculated at 0.000 million units (0.000% of the estimated 0.000 million units)
8:27:54 PM: Importance volume surface area calculated at 0.000 million units (0.000% of the estimated 0.000 million units)
8:27:54 PM: Preallocated 0.0Gb for kDOP nodes and triangles
8:27:54 PM: Building kDOP took  0.00 seconds.
8:27:54 PM: Static lighting kDOP: 0 nodes, 1 leaves, 0 triangles, 0 vertices
8:27:54 PM: Static lighting kDOP: -1.#IO% wasted space in leaves
8:27:54 PM: kDopTree.Nodes        :     0.0Mb
8:27:54 PM: kDopTree.SOATriangles :     0.0Mb
8:27:54 PM: kDOPTriangles         :     0.0Mb
8:27:54 PM: TrianglePayloads      :     0.0Mb
8:27:54 PM: MeshInfos             :     0.0Mb
8:27:54 PM: Vertices              :     0.0Mb
8:27:54 PM: UVs                   :     0.0Mb
8:27:54 PM: LightmapUVs           :     0.0Mb
8:27:54 PM: Static lighting kDOP: 0 nodes, 1 leaves, 0 triangles, 0 vertices, 0.1 Mb
8:27:54 PM: Processing...
8:27:54 PM: EmitDirectPhotons complete, 0.000 million photons emitted in 0.1 seconds
8:27:54 PM: EmitIndirectPhotons complete, 0.000 million photons emitted in 0.1 seconds
8:27:54 PM: Marking Irradiance Photons complete, 0.000 million photons marked in 0.1 seconds
8:27:54 PM: Caching Irradiance Photons complete, 0.000 million cache samples in 0.1 seconds
8:27:54 PM: Calculate Irradiance Photons complete, 0.000 million irradiance calculations in 0.1 seconds
8:27:54 PM: Lighting 100.0%

And my dxdiag

EDIT: Further information, I was using a beta AMD driver and suspected that might be it, but rolling back to 15.7.1 has not corrected the issue. I can provide the updated dxdiag if that would be helpful. Weirdly enough, I found a temporary workaround - if I add items to the scene (Static Mesh cubes) and restart the lighting build, I can improve the percentage that lighting builds to before hanging. When I get up to 10 cubes, the percentage hits 100% and the lighting build completes in seconds.

anonymous_user_6e7b421a · September 2, 2015, 2:12pm

Hey leonsbuddydave,

There is currently a known issue with these AMD 300 series cards causing users to crash. You can read the other posts about this issue below for more information.

We are currently in the process of getting these cards so we can test the issues on our end and get a fix implemented. Most of the users reporting the issue are using Windows 10 and DirectX 12 which are experimentally supported as it is still a very new OS.

“Microsoft’s engineers added support for DirectX 12 to UE4 and we have worked with them to integrate their changes into 4.9. The feature is still new and is considered experimental. DirectX 12 offers a much lower-level rendering API that is more efficient and allows for rendering commands to be submitted in parallel across many threads, a feature inspired by console rendering APIs. Going forward, we’ll continue to improve support for DirectX 12 and look for ways to leverage the new API in upcoming versions of the engine.”

The connections between these cards, the operating systems, and the DirectX version cannot be just coincidence. This is why we are trying to put together a machine to test these cards with these components. If you have any other questions please let me know. I will return here once we have been able to assess the issue.

Thank you,

jwatte · September 6, 2015, 4:19am

Well, this happens with a GTX 980, too, so it’s not just AMD…

anonymous_user_c1efc3ac1 · September 10, 2015, 1:34am

I have the same problem with a Quadro FX 4800…

Cerambyx_Cerdo · September 10, 2015, 6:10am

Same problem (but at 83%) with a GTX 770

anonymous_user_6e7b421a · September 10, 2015, 3:21pm

Hey guys,

Would someone experiencing this issue provide me with some reproducible steps so I can see this issue on my end in a new blank project?

Once I am able to see this issue, I can help troubleshoot and find a solution. One option you can try is to clean and validate your Swarm Cache which can be found in the swarm agent itself. Use the image below as reference.

Let me know if this helped or if you have further questions.

Thank you,

anonymous_user_6e7b421a · September 11, 2015, 6:22pm

Hey all,

I have gone ahead and entered a bug report for this issue (UE-20782).

There are other users who are experiencing and reporting this issue as well, and we appreciate your patience while we address and fix this issue. When the issue has been fixed and marked for an upcoming full release or hotfix, we will add it to our Documentation Release Notes section, or on the Announcements and Releases section on our Forums.

Thank you,

McDic · September 29, 2015, 7:28am

If there is huge Lightmass Importance Volume, all progress complete successful.

I don’t know deep programming knowledge so I’m not sure… But I just wanted to show in my case.