Cell Reference Counts and Performance in Oblivion

If you are running into fps issues with your mod, it can be useful to compare your cell ref count data with data from the vanilla Tamriel world space. This is especially worth checking if you notice your greatest fps drops in exterior, wilderness cells. Bear in mind that there is more to fps than simple reference counts. The 'weight' of the reference (eg. small, low-poly references vs. large, high-poly references) and the number of different reference types (eg. two different rocks vs. two of the same rock) impact performance as well. You also have to consider the number of actors executing AI packages, the number and 'weight' of the scripts you are running.

Output Cell Ref Counts

This is an option in the worldspace menu. It prints a tab delimited text file containing reference counts for all of the cells in the selected world space. Useful for testing performance and identifying 'heavy cells'. To print the cell ref count report, go to World -> World Spaces... and then select the world space you would like to print the report for from the World Spaces dialogue and click on the Output Cell Ref Counts button. The report will appear in your Data folder. You might want to convert the file to a spreadsheet for ease of use.

The columns break down as follows:

  1. X Coordinate
  2. Y Coordinate
  3. Cell Name
  4. Num of Refs in Cell
  5. Num of Refs that are Trees
  6. Num of Refs in Cell + 8 Surrounding Cells
  7. Num of Refs in Cell + 8 Surrounding Cells that are Trees
  8. Num of Refs in Cell + 8 Surrounding Cells + 16 Cells Surrounding These (ie. 5x5 cells, the default number of cells loaded at one time beyond which only LOD is loaded)
  9. Num of Refs in Cell + 8 Surrounding Cells + 16 Cells Surrounding These that are Trees

I've included some sample reference data below, including a table that shows the highest values from the sample data. This should give you some idea of appropriate reference counts for your own mod.

Cell Reference Count for the Tamriel World Space
X Coord Y Coord Cell Name Refs Trees Refs 3x3 Trees 3x3 Refs 5x5 Trees 5x5
0 0 Wilderness02 170 30 1671 322 4161 779
0 1 Wilderness 135 29 1468 286 3782 776
0 2 Wilderness 252 26 1219 267 3166 726
0 3 Wilderness 58 29 1083 247 3078 719
0 4 Wilderness 115 27 967 253 2928 701
36 41 Wilderness 8 0 192 23 611 116
36 42 Wilderness 20 20 142 89 673 273
36 43 Wilderness 27 27 181 181 599 407
36 44 Wilderness 38 38 244 244 600 526
36 45 Wilderness 31 31 250 250 677 643
Highest Reference Counts for the Tamriel World Space
X Coord Y Coord Cell Name Refs Trees Refs 5x5 Trees 5x5
0 2 Wilderness 252 26 3166 726
36 44 Wilderness 38 38 600 526
0 0 Wilderness02 170 30 4161 779
0 0 Wilderness02 170 30 4161 779

Last updated July 20, 2011

© 2009-2011 Dave Finch