I have the following kernels installed:
- linux-zen (Zen)
- linux-rt (RealTime)
- linux-hardened (Security Hardened)
- linux-lts (Long Term Support)
- linux-tr-lts (Realtime LTS)
When I boot up, I try the different kernels from time to time just to see if anything interesting happens. It never does.
My question: How do I actually physically notice the difference between these kernels? If I use RT, does Firefox spawn quicker (in my testing, no, not really)?
What are some use cases when I can really see the difference in these kernels?
Realtime is not about being fast, it’s about time guarantees. It helps with or is required for workloads that require realtime, which I think includes audio production, but might also be helpful for things like controllers etc. where you need to make sure incoming data is processed in a guaranteed time or else fail. Browsing the web isn’t part of these, so an RT kernel will most likely be a hindrance.
I think realtime is on mainline now since 6.12 though so anyone with at least 6.12 should be able to use rt functionality.
Yes, aircraft for example. If the pilot says “gear down”, the gear must go down in short order. You can’t say “well I think I’ll check the airspeed sensor a few times first”.
But it’s used in PES (Passenger Entertainment Systems) at least.
That’s pretty cool. Seems like a big undertaking tho
Ok this discussion reminds me of a gripe: Is there a Linux distribution or kernel that prioritizes the UI over everything else, including an OOM situation?
I’ve never had (modern) Windows kernel panic on me, or completely slow to the point I can’t get Ctrl+Alt+Del registered.
Let me know if I’m just using Linux stupidly though…
There’s a systemd OOM service that can be setup. I use CachyOS and they have it as a checkbox to turn it on or off.
Going to look into this, thanks!
I’ve had this exact same gripe and can thankfully report that running EarlyOOM has fixed this for me.
I’ve definitely had Windows hard lock before and stop responding to the keyboard, from Win95 all the way to Win10. I have no experience with Win11 so I can’t speak for that, but all others have situations where it can happen.
In fact, Windows is bad enough that the disk usage being high can cause the system to stop responding until it’s done and drops back down.
I thought that’s what Zen was for
Yeah I’ve had multiple times where a silly process (usually a game running via WINE) will shit itself and lock the whole desktop. it’s my only gripe even if it’s rare
Difference goes from negligible to imperceptible. They were only really necessary for back in the day specific use cases like digital audio latency.
Have you given the CachyOS kernel a try? It’s got some of the Clear Linux patches and some other custom patches, and it might have slightly better performance than the others you’ve listed here
Although expect to only really see any noticeable improvements in games or benchmarks and the like
Most of them won’t be that different when you’re not running anything that’s pushing your system to its limits. Zen might be a bit faster in games or benchmarks, RT really won’t do much unless you’re running software that needs Real-time processing (you shouldn’t use it for general use).
Hardened and zen are the only ones you might benefit from, but not really massively.
I don’t think there will be a noticeable difference. Real Time kernel is intended for things like microcontrollers I believe.
Realtime is important on fully fledged workstations where timing is very important. Which is the case for a lot of professional audio workloads. Linux is now another option for people in that space.
Not sure Linux can run on microcontrollers. Those tend to not be so powerful and run simple OSs if they have any OS at all. Though this might help the embedded world a bit increasing the number of things you can do with things that have full system on chips (like the Raspberry pi).
So it’s more for dealing with hardware interruptions quickly, and likely will not help with gaming?
