What happened to "File Headers" in build size on Unity3D 3.5

Questions & Answers
1

Hello

My project build size(on Unity3.4):

Textures      75.2 mb	73.3%
Meshes        6.9 mb	6.7%
Animations    3.3 mb	3.3%
Sounds        5.6 mb	5.4%
Shaders       128.2 kb	0.1%
Other Assets  3.9 mb	3.8%
Levels        396.9 kb	0.4%
Scripts       896.0 kb	0.9%
Included DLLs 3.9 mb	3.8%
File headers  2.3 mb	2.2%
Complete size 102.5 mb	100%

And it changed in Unity3.5 like this:

Textures      99.0 mb	61.9%
Meshes        6.8 mb	4.3%
Animations    3.3 mb	2.1%
Sounds        5.6 mb	3.5%
Shaders       148.5 kb	0.1%
Other Assets  4.3 mb	2.7%
Levels        1.2 mb	0.7%
Scripts       922.3 kb	0.6%
Included DLLs 3.9 mb	2.5%
File headers  34.7 mb	21.7%
Complete size 160.0 mb	100%

Please ignore other resources’ size, focus on “File headers”.
Do you guys have any idea? I think it’s related to count of files in “Resources”, but I’m not sure…

Please help. Thanks

2

We have recently received this question thru our support system, and we are in the process of enhancing the documentation. I’ll copy the answer here since it will help other users searching for this our community:

File headers is data that is kept maintaining references and settings for the assets, such as resource assets. It is the amount of extra data apart from the “raw” data contents in a file. Do you have assets in the “Resources” folder? You can try moving some or all files out of this folder and see if that reduces the file headers.