vivo's Linux Kernel Innovation at the 19th China Linux Kernel Developer Conference

This article reports on vivo's technical innovations and open-source contributions presented at the 19th China Linux Kernel Developer Conference (CLK). With the theme "Freedom, Collaboration, Innovation," vivo participated with 9 topics, showcasing significant advancements in Linux kernel technology.

AI On-Device Large Model Challenges: vivo's AI capabilities now cover over 60 countries and regions, serving more than 500 million mobile users, with over 3 trillion tokens generated. To address the challenges of large model memory requirements and limited UFS bandwidth, vivo implemented DMA-BUF DIO support and parallel optimization of file reading and memory allocation, achieving a 65% performance improvement in model file loading.

Memory Optimization: In the memory forum, vivo presented "ZHP (Zero-page Huge) Optimization" - introducing a multi-level compression state concept that categorizes memory pages into different compression states (ZHP, ZMP, ZSP) based on anonymous page data types, significantly improving memory compression efficiency.

Filesystem Optimization: In the Storage I/O forum, vivo showcased several innovations: EROFS filesystem memory minimization and allocation latency optimization; Zoned Storage solutions addressing write amplification and unpredictable I/O latency issues through new GC and OVP schemes; and f2fs large folios support that improved buffer write performance by 50.8%.

I/O Optimization: Solutions including Device Mapper for reducing flush and verity latency, and DMA-BUF Direct IO support to minimize system I/O resource consumption.

New Filesystem Features: Next-generation compression technologies including cluster variable-length compression and block fixed-length output compression; Inline tail technology to reduce f2fs small file space occupation.

All these kernel innovations have been contributed to the Linux kernel community, demonstrating vivo's commitment to open-source collaboration and advancing Linux kernel technology globally.