All the way up to 4PM I did some good work, creating a new task slicer for the lightmapper which will conserve the system memory even for massive levels. It does this by only lightmapping a chunk at a time, and then freeing up the used memory for the next job. I also found and fixed a few major memory leaks in the lightmapper too which helped hugely. Once I moved from my test scene to The Escape level, although it lightmapped fine as a single process, the sliced one now exhibits a very unique bug, which flashes the monitor (not the back-buffer of the app but the whole PC), and after ten seconds the whole machine freezes completely. Have to hard reset to get it back! Not a fine ending to the day, but I will go through line by line and fine the culprit but it will have to be Thursday now.
I also managed to do an updated trace of all the CPU allocations when running the map editor, and also tacked on the lightmap resource usage from this morning.
Ignore the title, it should have read "CPU System Memory" but you can see the worst offenders are terrain, and the 21% is the memory created during the light mapping process itself (along with some other big LM chunks). I am sticking with the lightmap resources for now as part of the ambient occlusion mapping work and then I will probably explore the terrain usage after I've done the priority performance tasks on my list.
It's a nice feeling when you finish a day and you've made progress and the software runs better than the day before. On this occasion, progress definitely made, but with a bug that literally forces a PC reset, I don't have that take-home feel good factor. I may return this evening for a few more hours and at least find and fix the 'freeze my PC' feature, as I don't want that to greet me come Thursday!!