CPU 100% when render.

I uploaded my stl file. (41M)
The CPU is very high 100%

Please see image and my file.
![image](https://user-images.githubusercontent.com/5344180/167784713-510e03ad-79ea-4fb9-ba3a-47f2f17650a8.png)

[Head1.zip](https://github.com/omrips/viewstl/files/8667349/Head1.zip)

