An example method and an example apparatus for writing data into a cache are described herein. The example method includes receiving an IO request write command, where the IO request write command includes metadata of to-be-written data. A first buddy group is obtained from a global buddy queue, and a determination as to whether all metadata of the to-be-written data can be written into the first buddy group is made. If the determination is yes, all the metadata of the to-be-written data is written into the first buddy group, and all the metadata of the to-be-written data is written into a metadata block corresponding to a metadata group to which the first buddy group belongs.