In the upcoming Linux 7.2 kernel version, the exFAT file system has completed the conversion to the IOmap infrastructure, bringing significant performance improvements and simultaneously introducing a series of fixes and code optimizations.
Namjae Jeon, a developer who has long maintained the Linux kernel exFAT file system code, is also the maintainer of the new NTFS driver. He completed the adaptation of the exFAT driver to IOmap in this round of integration. Currently, the exFAT driver on Linux has been migrated to use IOmap to handle buffered I/O (buffered I/O), direct I/O (direct I/O), and operations such as SEEK_HOLE/SEEK_DATA in LLSEEK. IOmap is a general framework in the Linux kernel for mapping file logical offsets to physical storage blocks. The goal is to replace the buffer head mechanism previously used in the kernel and uniformly handle common file operation logic in multiple file systems.
According to the patch notes submitted to the kernel mailing list, after changing common exFAT operations to rely on IOmap, "very good performance improvements" were achieved in the performance benchmark test. The official also summarized the test results as "the performance improvement is very impressive." Although specific numerical details were not disclosed in the news, judging from the overall performance of the benchmark test, the throughput and response of the new version of exFAT have been significantly improved in a variety of typical scenarios.
This set of exFAT patches that have been merged into Linux 7.2 includes not only IOmap conversion, but also multiple bug fixes and code quality improvements. For users who frequently use exFAT (such as USB flash drives, removable memory cards and other removable media) on Linux, the performance benefits brought by IOmap alone are enough to become one of the important reasons to upgrade to Linux 7.2.