The reasons are as follows: firstly, it may have been optimized and released a part of the occupied memory.

Second, there are patches coming out constantly, and the capacity will indeed expand slowly.

You can try to lose weight. After the following two operations, it basically occupies 10G space.

First, transfer the virtual memory to the system disk to "lose weight"

In order to improve system performance and speed up system operation, Windows system provides virtual memory mechanism, while in Windows7 system, virtual memory is turned on by default, and virtual memory files are stored in the system disk by default, and the file size is equivalent to the memory size configured by the computer. We can "lose weight" by transferring virtual memory out of the system disk.

Move the mouse pointer to the desktop computer icon, click the right mouse button, and select Properties in the pop-up shortcut menu to open the system window. Click the "Advanced Settings" text link on the navigation bar on the left side of the window to open the "System Properties" window, switch to the "Advanced" tab, and click the "Settings" button on the right side of the performance bar to pop up performance options. Open the virtual memory window, remove the √ in the "Automatically manage paging file size of all drives" selection box, select a partition other than the system disk (such as D disk) in the disk list, and then select "Custom size" to set the initial size and maximum value of virtual memory, or select "System management size" to let the system automatically manage the size of virtual memory, and finally click "Set".

Second, turn off the hibernation function and "slim down" the system disk.

There is a hibernation function in Windows7 system, which can write all the data in the memory to the hard disk, then shut down the system, and then write the saved data back to the memory at the next boot. The advantage of this is that all the work in progress will be saved, and it can be restored even if there is unexpected power failure, at the cost of occupying the same space as the memory on the system disk. If you don't need this function, you can turn it off, free up disk space and "slim down" the system disk.

Log in as a system administrator, click Start → Run to open the running window, enter "CMD" (without double quotation marks) in the text box, press enter to open the command prompt window, enter "powercfg-hoff" (without double quotation marks, preceded by a space -h, and close), and press enter to close Windows7 system hibernation. If you want to restart the system hibernation function, enter "powercfg-hon" (excluding double quotation marks, with spaces and on before -h) in the Command Prompt window, and then press enter.