lightcache and large render sizes

ive found that on renders above a certain size, lightcache becomes agonisingly slow and uses about 5% processor… anyone else experienced this?

on my current project (medium complexity, couple of million faces, one light, exterior, using lightcache for secondary only) i can render a 1600 x 1200 image and the lightcache uses 100% processor and takes about five minutes to complete. if i bump up to 2500 x 1500, the lightcache takes 2+ hrs (i never let it finish) and sits at about 1 - 5% processor the whole time…

im using 1.47.03, but have had this issue for several versions…

usually anything over 2000 pixels i use split rendering. normally my average renders are about 3000 or 5000

super gnu, disable the preview of the light cache calculations and it should be fine.

Best regards,
Vlado

thanks a lot guys.