[pve-devel] Plans for Realtime Kernel and Realtime Configuration Support in Proxmox?

[Fabian Grünbichler]

> Florent Carli via pve-devel <pve-devel at lists.proxmox.com> hat am 06.06.2025 10:22 CEST geschrieben:
> Hello,
> 
> After trying the user forum first, I'm turning to you here. I did a
> quick Google search to make sure the question hadn't already been
> answered (apparently not). Now I'm reaching out to the real experts :)
> 
> I’m currently exploring Proxmox for some use cases that require
> low-latency and deterministic behavior - particularly in the context
> of real-time workloads. I’m wondering if there are any current plans
> or ongoing discussions around:
> 
> - Supporting a real-time kernel (e.g., with the PREEMPT-RT preemption model).

a lot of the RT patch set got merged in 6.12, but we currently don't plan on
shipping a separate RT-optimized set of kernel packages. the sources are there,
so evaluating your own kernel build with custom KConfig values should be fairly
straightforward.

> - Enabling and integrating real-time system configurations, such as:
> - Integrated workflows for CPU isolation, IRQ affinity, and low-latency tuning
> - vCPU pinning, and using real-time scheduling policies (e.g.,
> SCHED_FIFO, SCHED_RR)
> - Integration or support for tools like tuned to do the kernel
> configuration customization options relevant to RT
> - Integration with PTP...

better support for vCPU/iothread pinning, affinity settings and various
scheduling optimizations are planned or being worked on, but those mostly
happen in the context of perf and resource usage optimization, not RT
workloads. I do suspect a lot of that work can serve as a baseline for
doing your own optimizations.

for both kernel and user space the issue is that many optimizations that
improve RT performance can either change or hurt performance characteristics
for "regular" usage.

> Are there any official efforts or community-led initiatives in this
> direction? And if not currently on the roadmap, would this be
> something of interest to the Proxmox team or the community?

in particular for features/settings that are of interest across the board,
feel free to file enhancement requests on bugzilla.proxmox.com, ideally
with reference configs and benchmark results!

thanks