# Updating a packaged game with chunks, how to know which pak changed? **URL:** \ **Category:** Platform & Builds\ **Tags:** pak, Chunking, unreal-engine, update, question\ **Created:** [May 1, 2024, 9:04pm UTC](https://forums.unrealengine.com/t/updating-a-packaged-game-with-chunks-how-to-know-which-pak-changed/1835429 "2024-05-01T21:04:03Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![dschertenleib](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@dschertenleib](https://forums.unrealengine.com/u/dschertenleib)\ **Post date:** [May 2, 2024, 8:31pm UTC](https://forums.unrealengine.com/t/updating-a-packaged-game-with-chunks-how-to-know-which-pak-changed/1835429/2 "2024-05-02T20:31:35Z")
So it seems unreal is changing the load order of the files in a pack to optimize opening speed If you do not specify an order, i will use the data you generate when working in editor/play Disabling it for now fixes part of the issue but i still had packages change in size: > [@Different .PAK files for same packages?](https://forums.unrealengine.com/t/different-pak-files-for-same-packages/1278732/7): > > Hi there. I had the same issue and just found a solution. There is no documentation to find anywhere about how the ordering works, but looking into the source code I was able find it out. So, if you don’t have a GameOpenOrder.log it will automatically fall back to CookerOpenOrder.log and EditorOpenOrder.log. These 2 files are changed permanently and therefore cause assets being differently ordered in paks. Even if you had a GameOpenOrder.log in place, it would fall back to the other ones for … After that i did find by comparing 2 paks that some .ushader files did change… Enabling “Deterministic shader code order” did improve but did not get rid of all the issues so i did disable “Share Material code” for now. It seems to do it, i will run more tests ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/d/b/adb08e9c59fa82dc73a4f989d44db1ae45e3057e.png) --- _[View the full topic](https://forums.unrealengine.com/t/updating-a-packaged-game-with-chunks-how-to-know-which-pak-changed/1835429)._