After two months of development, Linus Torvalds presented the release of the nucleus linux 5.19 . Among the most noticeable changes: support for the Loongarch processor architecture, the integration of the Big TCP patches, the ON-DEMAND mode in fscache, removal of the A.OT code to support the ZSTD to compress the firmware, the interface to manage memory displacement from the user space , increasing the reliability and performance of the generator generator, support for Intel IFS (In-Field Scan) extensions, AMD SEV-SNP (Secure Nested Paging), Intel TDX (Trusted Domain Extendns) and ARM SME (Scalable Matrix Extensive).
In the announcement, Linus said that most likely the next release of the nucleus will be assigned number 6.0, since in the 5.x branch sufficient issues to change the first number in the version number. The change of numbering is carried out for aesthetic reasons and is a formal step that relieves discomfort due to the accumulation of a large number of issues in the series.
Linus also mentioned that he used the Apple laptop based on the ARM64 architecture (Apple Silicon) with Linux-contribution based on the ASAHI Linux distribution. This is not the main workstation of Linus, but it used this platform to check its suitability for working on the core and be sure that he could form the nucleus on the trip, having a light laptop on hand. Before that, many years ago, Linus had experience using Apple equipment for development – once it used a computer based on the CPU PPC970 and the MacBook Air laptop.
basic innovations In the nucleus 5.19:
- disk subsystem, input/output and file systems
- Erofs file system (Enhanced READ-ONLY File System), designed to use in sections available in reading mode, translated on the use of the FSCACHE subsystem that provides data caching. The change made it possible to significantly raise the performance of systems in which a large number of containers are launched from the image based on EROFS.
- In the subsystem fscache added Reading mode (“On-Demand”), which is involved in the optimization of EROFS. The new mode allows you to organize reading from the images of FS in the local system. Unlike the initially available mode of operation, focused on caching in the local file system transmitted through network file systems, the “On-Demand” mode delegates the functions of data extraction and their records in the cache with a separate background process performed in the user’s space.
- In the XFS, it is possible to store billions of expanded attributes in I-Node. The maximum number of extras for one file is increased from 4 billion to 2 47 . implemented