SMP & Interrupt Affinity

Message
Author
User avatar
Stevo
Forum Veteran
Forum Veteran
Posts: 10945
Age: 57
Joined: Fri Dec 15, 2006 8:07 pm

Re: SMP & Interrupt Affinity

#11 Postby Stevo » Thu Oct 20, 2011 9:46 pm

The Liquorix kernel adds the Zen kernel patches. http://zen-kernel.org/ The same fellow maintains those and the Liquorix kernel, and has an account here as "damentz", though the Liquorix forums is probably a better place to ask technical questions.

In our community repository, http://main.mepis-deb.org/mepiscr/repo/ ... uorix-2.6/

the original kernel source is in the orig.tar.xz file. There's a folder that gets added to the source to "debianize" it, in this case it's the xxx_debian.tar.bz2 file. If you manually extract it, you will get a /debian folder, and inside it a /patches folder that has the patches that get applied to the source to create the Zen source. The kernel config file is also in the /debian folder.

The Liquorix kernel is meant to be more responsive and have low-latency (good for audio work). It also has possibly different process schedulers, such as the BFS one, that are not in the vanilla kernel. Distributing the load between processors probably keeps them cooler overall, though it's hard to measure that.
The optimist proclaims that we live in the best of all possible worlds, and the pessimist fears this is true.

James Branch Cabell

User avatar
Saist
Forum Regular
Forum Regular
Posts: 797
Age: 34
Joined: Sat Jul 15, 2006 10:57 am

Re: SMP & Interrupt Affinity

#12 Postby Saist » Fri Oct 21, 2011 10:22 am

Stevo wrote:The Liquorix kernel is meant to be more responsive and have low-latency (good for audio work). It also has possibly different process schedulers, such as the BFS one, that are not in the vanilla kernel.

When it comes to the BFS scheduler, the term "snake-oil" comes to mind. For starters the BFS scheduler really doesn't post any gains under system benchmarking when compared to the CFS scheduler. Typically the lack of benchmarks to show that BFS actually does anything is met with responses that BFS is "about the feel of the system" rather than any specific response time or measurable priority usage. However I've never been able to create any situation with any x86 processor; including Atom, Phenom AM2, Phenom II AM3, I7, Celeron D, A64 754, A64 939; where a kernel using BFS provided any noticeable improvement over the same kernel using CFS. The few times I've run a "blind" test where the person I grabbed to sit at the keyboard and do stuff, they thought the kernel with the CFS was more responsive.

The impression I get with BFS is that people claim BFS is more responsive or better than CFS because they are -told- it's more responsive or better than CFS.

I suspect that might also be why the main author behind BFS, Con-Man Kolivas, is extremely disinterested in having the scheduler looked at by Ingo, or any of the CFS scheduler contributors at IBM or Google.


Return to “Hardware / Configuration”

Who is online

Users browsing this forum: No registered users and 1 guest