Lightmass: multi-bounced sky lighting

He everyone!

I’m using 4.23.1 and I try to build project with CPU (lightmass: mulit-bounced sky light, bUseFilteredCubemapForSkylight=false). But Building time going very slowly (has gone over 10 hours and still 0%)

And I want to ask “is this normal?” or I did something wrong.

Please help me.
Thanks