Metahuman Animator stalls during Prepare for Performance

[Doraemon231]

@JaneHaslam

On a lower spec machine (either in terms of RAM or CPU), ‘Prepare for Performance’ can take a while, possibly as long as half an hour. This part of the processing uses a lot of memory; if you have less than 64Gb of RAM it will perform the processing in a less memory-consumptive way which takes considerably longer to run. Basically, if you are still seeing significant CPU usage, the process has not stalled and should eventually complete. Even on a reasonably high spec machine, this process can take around 20 minutes or so.

There is one additional non-standard trick which can be used to speed things up on a low-spec machine (either in terms of RAM or CPU). If you set the following CVar: mh.Identity.TrainPreviewSolvers false, it will not train the preview solvers to be used in the Performance asset. When you process the Performance, you must then check the Processing Parameters->Skip Preview property before processing the shot, otherwise you will get an error message saying that the MetaHuman Identity has not been prepared to process performances. Skipping Preview will not affect the quality of the final solve (assuming you have selected either Standard or Additional Tweakers Solve Type); it simply means that the first solve ‘preview’ pass will not display any results.

If you are still hitting problems, please reach out and we will investigate further.

Please explain in a bit more detail.
What can I do to disable the preview?