Why do EXT2 file systems need to be divided into multiple block groups?

Why do EXT2 file systems need to be divided into multiple block groups? -- Linux general technology-Linux technology and application information. For details, refer to the following section. Look at laruence's Private food...

File System => super block => block group 1 => super block, group description, block bitmap, inode bitmap, inode, block data
=> Block group 2 => super block, group description, block bitmap, inode bitmap, inode, block data


Isn't it all about dividing a block group? Block bitmap and INODE bitmap. Do you want to increase the bitmap?

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