What is the F2FS file system?
F2FS, which stands for "Flash-Friendly File System," is a file system specifically designed for NAND-based flash storage devices like solid-state drives (SSDs), eMMC storage, and SD cards. It was developed by Samsung Electronics and is open-source, available under the terms of the GNU General Public License (GPL).
F2FS was created to address some of the challenges and limitations posed by traditional file systems, such as ext4 or NTFS, when used on NAND flash storage. NAND flash storage has characteristics that differ from traditional hard disk drives (HDDs), and F2FS is optimized to make the best use of these flash storage features. Here are some key features and characteristics of the F2FS file system:
Flash-Friendly Design: F2FS is tailored to the idiosyncrasies of NAND flash memory, which has characteristics like wear leveling, erase-before-write requirements, and the need to minimize write amplification. The file system's design takes these factors into account to prolong the lifespan of flash storage and maximize performance.
Log-Structured: F2FS uses a log-structured design, which means it writes new data to append-only logs rather than overwriting existing data blocks. This approach minimizes random writes, which are detrimental to NAND flash memory's performance and longevity.
Segmentation: The file system divides the storage into segments, which are independently manageable units. Segmentation enables efficient garbage collection and wear leveling, both of which are essential for NAND flash storage.
Checkpointing: F2FS uses a checkpoint mechanism that helps recover from system crashes more quickly and reduces the chances of file system corruption.
Inline Data Compression: F2FS supports inline data compression, which can save storage space and improve read and write performance, as less data needs to be transferred between the storage medium and memory.
Trim Support: F2FS supports the TRIM command, which helps the file system inform the storage device about unused blocks, allowing the device to perform better garbage collection and wear leveling.
Multiple Device Support: F2FS has support for multiple storage devices, making it suitable for use in RAID configurations or on systems with multiple storage devices.
Linux Kernel Integration: F2FS is integrated into the Linux kernel, making it readily available for Linux-based operating systems and distributions.
F2FS is particularly well-suited for devices and systems that rely on NAND flash memory as their primary storage, such as smartphones, tablets, embedded systems, and SSDs. It offers advantages in terms of performance and longevity compared to traditional file systems when used on NAND flash storage. However, it may not be the best choice for systems with conventional hard drives or certain types of workloads, where other file systems like ext4 or XFS might be more appropriate.