What's Happening?
An Amazon/AWS engineer has reported a significant performance regression in PostgreSQL when running on the Linux 7.0 development kernel. The throughput for PostgreSQL is reportedly halved compared to previous kernel versions, attributed to increased time
spent in a user-space spinlock. The issue has been traced to changes in the kernel's preemption modes, specifically the restriction to full and lazy preemption models. A patch has been proposed to restore the PREEMPT_NONE model to address the regression, but it may not be adopted, suggesting PostgreSQL may need adaptation.
Why It's Important?
This performance issue is critical for businesses and developers relying on PostgreSQL for database management, as it could lead to decreased efficiency and increased operational costs. The regression could impact the adoption of Linux 7.0, especially for enterprises using PostgreSQL, potentially affecting the broader Linux ecosystem. The situation underscores the importance of thorough testing and adaptation of software to new kernel versions, highlighting challenges in maintaining performance across updates.
What's Next?
With Linux 7.0 stable release imminent, stakeholders must decide whether to implement the proposed patch or adapt PostgreSQL to the new kernel environment. The decision will affect PostgreSQL's performance and user experience. Developers and businesses may need to prepare for potential updates or workarounds to mitigate the performance drop. The outcome will influence future kernel development and PostgreSQL's adaptation strategies.
