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zlib Updated - NVSE Mod

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zlib Updated - NVSE mod for Fallout: New Vegas
Uploaded23 Feb 2026
Version1.1
98.44 KB
Total Files Sizes
1
Unique DLs
1
Total DLs
1
Total Files

zlib Updated - NVSE

File Size98.44 KB
Game Image for Fallout: New Vegas
2
Performance Optimization


What?

Game uses zlib compression for BSAs, NPC and Landscape records. While you can decompress those, most mod authors don't.

Why is that an issue? Zlib is super slow to decompress, which leads to longer loading times and stuttering.

On top of that, game obviously uses a super old zlib version (1.2.1), which doesn't help.


I was bored, and decided to upgrade it to the latest version (1.3.1 at the time of writing), and to my surprise, it's about 2 times faster.


Does that mean that you should compress all BSAs now? No, the decompression time is still super slow.

Does that mean that you *can* compress BSAs without being scared of freezing the game every time a cell is loaded? Yea.


FYI, record compression is disabled by the latest GECK Extender.


Decompression stats:

Time it takes to decompress files and records


Mojave Express Guide - Vanilla: 64 7.725ms (total) | 0.688ms (avg time per file)

Mojave Express Guide - Updated: 324.249ms (total) | 0.344ms (avg time per file)


Decided to check with vanilla BSAs as well:

Mojave Express Guide - Vanilla: 4111.904ms (total) | 0.778ms (avg time per file)

Mojave Express Guide - Updated: 2130.654ms (total) | 0.403ms (avg time per file)

So yea, you still have to decompress stuff


Loading time data:

Time it takes to load - from main menu, to in-game.

Mojave Express Guide:

Vanilla zlib: 9578.195ms

Updated zlib: 9024.290ms

Uncompressed: 8796.764ms


Vanilla game:

Vanilla zlib: 8862.736ms

Updated zlib: 6399.111ms

Uncompressed: 5155.468ms


Source Code

GitHub


Credits

Jean-loup Gailly and Mark Adler for creating zlib

Instructions

Updates zlib to the latest version for faster loading and less stutter.

Requirements

Permissions and credits

No permissions have been set

zlib Updated - NVSE

Type: Main
Date uploaded23 Feb 2026
File Size98.44 KB
Unique DLs1
Total DLs1
Version1.1

The mod itself