Linux 7.0 faces potential delay amid postgresql performance hit
Linus Torvalds is reportedly far from pleased with a recently discovered issue threatening the release of Linux 7.0. Just days before the eagerly anticipated kernel update was slated to arrive, a significant snag has emerged, potentially jeopardizing the timeline.
A critical performance degradation
After a tumultuous period of RC releases plagued by numerous bugs, things seemed to be stabilizing. Now, it appears that calm has been shattered. A test conducted by engineers at Amazon Web Services revealed a nearly 50% performance reduction in PostgreSQL – a database system ubiquitous across businesses and individual projects alike. This isn't a minor inconvenience; it’s a potential cascade effect impacting countless services.
The root cause? A deliberate removal of the PREEMPT_NONE kernel option, designed to optimize processor task management. Early testing indicated up to 55% of CPU time was being lost in internal waits, effectively crippling processing power. It’s a classic case of short-term gains leading to long-term pain, and a particularly thorny problem for the Linux development team.
A difficult balancing act
The immediate solution – reverting the change – presents a monumental challenge. Reversing this week’s substantial kernel work would essentially undo weeks of effort, and wouldn’t address the underlying issue, which could resurface with future modifications. Instead, developers are exploring an alternative: adapting PostgreSQL itself, specifically by implementing a different time management system, dubbed rseq. However, this isn’t a simple swap. Integrating rseq requires urgent updates to PostgreSQL, a process that may not be feasible within the tight timeframe leading to Linux 7.0’s release.
The projected release window, previously a reliable 10-week cycle from rc1, is now subject to considerable uncertainty. Estimates suggest a stable version could arrive as early as April 5th, 12th, or 19th, depending on the number of required Release Candidate iterations. Rolling release distributions will likely receive the update almost immediately, while those opting for a more cautious approach – like Ubuntu 26.04 – will need to wait. Mainline, a tool facilitating the installation of diverse kernel versions, allows interested users to independently verify the system’s state, providing a crucial early warning system.
Despite these complications, there’s currently no indication of a delay. The roadmap anticipates a stable release by mid-April 2026, following a roughly 10-week development cycle. The final release date – April 5, 12, or 19 – hinges on the number of required RC iterations. For those seeking a firsthand look, attempting Linux 7.0-rc7 via Mainline is a viable option. To install it, use the command: sudo add-apt-repository ppa:cappelikan/ppa && sudo apt update && sudo apt install mainline. Ultimately, this setback highlights the inherent risks associated with pushing the boundaries of kernel development, a constant tightrope walk for the Linux community.