PREEMPT_RT Q&A with tglx
summary
Q&A lists concrete blockers: getting printk real-time done, then converting a few hundred console drivers and enabling the switch before tackling lazy preemption. Networking hits a softirq bottleneck for TSN where XDP zero-copy helps but TX permission issues prevent full offload. Reader-writer locks bite real workloads — epoll broken from unfair rwlocks — and three approaches target VM locking: per-VMA lock bit (Suran B), maple tree layout, and speculative RCU page-faults with reported single-digit to ~70% speedups depending on the patch. Proxy execution and summing scheduler weights across cgroups remain open.
AI-written summary · about
chapters (8)
- 0:00Printk and kernel updates
- 1:28Roadmap and pending tasks
- 3:35Softirq and network issues
- 6:37Locks and priority inversion
- 9:46Epoll and architecture
- 14:06Memory management improvements
- 16:21EBPF integration status
- 17:38Scheduling and wrap-up
