Developer Notes

This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.


There is a setting called "LocalJobsDefaultProcessorCount" in the Developer Settings tab in Swarm. After the change to make Lightmass build asynchronously while the user keeps working, this setting doesn't do anything. (Update: it looks like this setting has gone away)

Instead, there is a setting in BaseLightmass.ini:


That number represents how many processor cores will not be used for building lighting, and instead will be dedicated to the Editor. So setting that to 1 means that all but one of your cores will be used to build lighting. The user should be able to set this setting in a proper UI somewhere. Maybe this should now be in the Editor instead of in Swarm?

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Won't Fix
ComponentUE - Graphics Features
Affects Versions4.
CreatedAug 25, 2015
ResolvedFeb 14, 2017
UpdatedApr 27, 2018