Solid-state drives (SSDs) that adopt flash memory have become one of the most popular storages. With the progress of the manufacturing process, a page size of flash memory has been increased from 512B to 16KB in recent years. However, an I/O request of current file systems could be based on a 4KB sector. Due to the difference between the 16KB page and the 4KB sector, there will be subpage writes in the flash memory. Although some previous studies have been proposed to solve the problem of subpage writes, we observe that there are two different methods to handle the subpage writes. Therefore, in the paper, we will propose a subpage-aware write method to solve the problem from the perspective of the buffer management and the mapping from logical page numbers (LPNs) to physical page numbers (PPNs) by utilizing the advantages of the two different methods to handle the subpage writes.

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