Windows 10 monthly patch size reduced by 20% ~ Improved after April 2024 preview patch – Window Forest

Preview patch “KB5036979” for Windows 10 version 22H2, released on April 23, US time, includes changes to reduce the size of cumulative updates (LCUs).

The monthly quality updates for Windows 10 are cumulative, meaning they include all patches released at that time. Therefore, for example, even if you forget to apply the March update, there is no problem if you apply the April update. In any case, all you need to do is apply the latest patch, and the system is easy to understand for end users.

However, the size of cumulative updates (LCUs) increases every month. Even if the size of each monthly update is about 100MB, if it is “accumulated” each month, it will quickly add up to GB.

Therefore, “KB5036979” introduces a new method to reduce the size of the LCU.

LCU consists of a pair of compressed differences between the base update program and the new update program (forward difference), and a compressed version of the opposite difference (reverse difference). The reason for the backward diff is to restore the original state when a patch is deleted, but it turns out that this is not always necessary. Therefore, they stopped including backward differences in the LCU at the stage of introducing Windows 11, and as a result, they succeeded in reducing the size by approximately 40%.

This approach will also be packported to Windows 10 starting this month. The LCU package size is expected to be reduced by about 20% in Windows 10, and the following benefits will be obtained.

• Reducing network bandwidth
• Faster downloads
• Reduce network traffic
• Improved performance on slow connections

Please note that this change requires image maintenance after the July 23, 2023 update (KB5028244), or the application of the standalone service stack update “KB5031539” (released October 10, 2023). It should be installed automatically, so it shouldn’t be a problem in a general environment.