I'm still waiting for proper big.LITTLE that isn't just coping. Intel has way too many E-cores -- you shouldn't need that many, but I think most of them would've been P-cores if Intel had die space and thermal efficiency to spare... Apple doesn't have that problem with M1, so they can do crazy things like 10 P-cores + 2 E-cores in a laptop, while Intel is just constantly bleeding E-cores trying to reach high core counts. Even Intel's very highest-tier flagship desktop options still don't have more P-cores than E-cores.
Not a big fan of Intel, but it does make some sense for them to use more E cores compared to Apple. My recollection is the perf delta between Intel E cores and P cores is a good bit smaller than on Apple’s M series chips. At the same time, their P cores are much less efficient than Apple’s. So the ideal mix for Intel is going to lean more on the E cores.
Based on my quick reading of this it doesn’t seem like the nesting structure explicitly takes into consideration the presence of efficiency cores. Am I missing something? How would this perform (in terms of latency, throughput, and power efficiency) on a hybrid CPU? Is this only meant for classic SMP and/or NUMA systems?
It also sounds like it doesn’t query the power states/frequencies and instead simply assumes a recently used core will be more efficient to use than idle one?
Is that correct and if so, why? Is it slow or inefficient to query power states at regular intervals? Or would it require more bespoke per-cpu code that you don’t want in a scheduler? That type of knowledge seems it’s still inevitable to schedule between big/little cores anyway?
It seems to be focused more on throughput-oriented workloads on large-bordering-on-exotic multi-node servers (e.g. 4-socket Xeons). It doesn't seem to have been evaluated at all in terms of latency (i.e. how long after a network request or other exogenous event arrives is a thread running on the CPU, and is that wakeup CPU selection optimal).
Interesting. I recently switched from arch to popOS, and one thing that I noticed was that my laptop no longer dropped frames watching 1080p youtube, and the subtitles do a better job keeping up at 2x speed. This is supposedly due to a different scheduler.
Granted, while I've got no hard evidence I'm thermal throttling, I probably need to reapply thermal paste. When I did that for an old laptop my temps dropped by 20c and it noticeably improved it's performance.
Yeah, I've been using linux for over 20 years, but I was pretty shocked by the number of sharp edges I encountered with arch. A recent update basically borked grub. On investigating the issue I found that the arch maintainers were shipping grub builds from the grub master branch, and when I pointed out this might not be the best idea the maintainer got huffy and said maybe I wasn't 'ready for arch'.
I installed popOS that day. I miss the AUR a bit, but pop resolves most of the issues I had with ubuntu, and starts and runs noticeably faster than arch, so all in all I'm pretty happy with it. It's a shame that arch can be so user hostile. I really admire it's wiki.
Arch is great as a hobby, the problems only come up if you also want to use your computer for other hobbies. I installed arch on my laptop back in 2010 and it was a worthwhile learning experience, but these days I use Mint with the Liquorix kernel and it's fantastic for regular desktop usage and gaming.
I recently switched from Arch to Fedora Silverblue. I have my terminal open directly into an Archlinux container created by Distrobox. In there I have all my usual bits and bobs installed from the main Arch repos, plus the aur. Even graphical stuff, like Sublime Music, which I export to the host. But you don't need to be running Silverblue. You should give it a shot on PopOS; it really makes you feel at home coming from Arch.
Do you mind listing what issues you have with Ubuntu compared to Arch (and which ones popOS fixes?)? As someone who's only ever used Debian-based distros, I've always wondered what problems Arch actually solves for people.
The main thing I disliked about ubuntu was the lack of availability of recent software, and the packaging of software in snaps. Used to be, deb packages was the 'lingua franca' of the internet. Everyone offered deb files, often provided by PPAs. These days you're much more likely to find a package in pacman / aur as ubuntu has gotten a little less popular amongst the folks who like playing with the bleeding edge.
Arch has pacman, which I found about as good as the ubuntu repos, but it also has AUR, which has damned near everything. Unfortunately, arch is also almost willfully hard to use. They only recently got an 'installer' and it's a shell script that's worse than the slackware installer I first used back in '99. There isn't very good tooling to tweak settings for anything, you're referred to the arch wiki, that, while good, could really use a technical writer. Finally, I strongly get the sense that it's a 'toy' distro meant for exploring than a production distro meant for prod use. Granted, this is mainly from my experience where updates failed spectacularly (twice!), and the devs responsible basically shrugged and blamed upstream, when they were making grub builds straight from master for their 'stable' repos. Their 'fix' took a whole week, and was basically adding some patch notes advising people to run a command before rebooting.
Pop OS is basically the latest ubuntu LTS with a few tweaks to gnome, a scheduler which gives higher priority to foreground tasks, and installs most major packages from deb repos instead of snaps (though flatpacks are still available. If not for pop i would have simply went with linux mint.
Not gp but was in the same boat... Only ever used Debian based distros...
1. No upgrade path between lts... You're on your own
2. On 20.04, no working Wayland, Bluetooth issues even with pw,
3. In general, PPAs don't come close to aur in terms of availability of sw
I was going to switch to arch, but after the grub issue noted in other comments here, went with manjaro since this is also my work machine
Manjaro has its own, different set of issues, but I've yet to hit any of them
So I'm not the only one bitten by the Grub issue. I haven't had time to properly look into it so far, and I don't use my ArchLinux machine too often, so I guess it will wait quite a while.
I switched to systemd-boot because I could not boot even after wiping all grub files, reinstalling and running grub-mkconfig. Worked fine in minutes with all my kernel entries and Windows.
Before that I tried rEFInd, wrote a small lean config file and while I could boot, I had some UI issues. Seemed buggy but it might have been my fault.
Want to say I've had good luck with rEFInd in my simple use cases, and the author Rod Smith is very active and helpful on the Stack Exchanges, if one runs into issues. His website is also one of the "last few" simple, content-oriented sites around. Thanks Rod.
https://www.phoronix.com/news/Nest-Linux-Scheduling-Warm-Cor...