The Completely Fair Scheduler was merged for the 2.6.23 kernel. One CFS feature which did not get in, though, was the group scheduling facility. Group scheduling makes the CFS fairness algorithm operate in a hierarchical fashion: processes are divided into groups, and, within each group, processes are scheduled fairly against one another. At the higher level, each group as a whole is given a fair share of the processor. The grouping of processes is done in user space in a highly flexible manner; the control groups (formerly 'process containers') mechanism allows a management daemon to classify processes according to almost any policy.
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Member since:2006-03-23
i also seem to remember not too long ago some freebsd benchmarks where the freebsd dude was deliberately using some software versions that had bugs when compiled on linux, and various misconfigurations, where when actually done properly, linux beat the living crap out of bsd 
Member since:2006-07-15
Maybe you should clean up your mind first.
1. some heavy bugs in Linux, discovered thanks to these benchmarks
2. prober configuration from the beginning with the help of some Linux developers
3. even today CFS is sometimes inferior to the new FreeBSD scheduler
4. just a note: NetBSD current beats Linux too, it's no miracle just proper software engineering
>where when actually done properly, linux beat the living crap out of bsd
Thanks god the members of LKML aren't such zealots :-)
Member since:2006-07-15
>Just read the FreeBSD-performance list, there are still cases where the "old" 4BSD scheduler performs better.
Just read it first before trolling around! Some bugs, nothing more, nothing less.
>Remember that CFS is still quite new.
Remeber this too for FreeBSD.
>the latest development code of the scheduler (most of which was merged for 2.6.24) already had some improvements.
Dear Linux zealot, the benchmarks were even in discussion on the LKML and lead to some positive development (your nice patches for CFS).
>Linux has been ahead (performance wise) for so many years
Yeah maybe in your very dreams. At high load Linux sucks for so many years (don't mention the 2.4 crap at all), even today with the latest CFS. Linux generated some hype about peaks and couldn't deliver a stable environment in terms of performance at high load. Linux is working with hype and error permissiveness, *BSD is working with quality and reliability in mind. So next time do your home work first. Btw. for all of these benchmarks always the latest patches were used, sometime with support of the Linux community from LKML.
Member since:2007-07-11
> Just read it first before trolling around! Some bugs,
> nothing more, nothing less.
Well, I guess you could say the same about CFS then? That there are still some bugs and once they get fixed it'll perform better.
> Dear Linux zealot, the benchmarks were even in
> discussion on the LKML and lead to some positive
> development (your nice patches for CFS).
Not quite true. Someone posted Jeff's latest results on LKML (Jeff was using 2.6.23) and then Ingo redid the benchmark with the latest development code for CFS and the results were better.
> Yeah maybe in your very dreams.
Please take a look at this:
http://people.freebsd.org/~kris/scaling/7.0 Preview.pdf
As you can see at page 11, FreeBSD 5.5 didn't scale at all, version 6.2 did a little better, but only for very few threads. 6.2 is still the stable version and Jeff published his first benchmarks of the new ULE scheduler in the beginning of 2007.
> Linux is working with hype and error permissiveness, > *BSD is working with quality and reliability in mind.
Yeah right... the old urban legends again. Linux is all crap and BSD is pure quality!
> Btw. for all of these benchmarks always the latest
> patches were used
You are wrong again. Jeff was using 2.6.23 and testing it against bleeding-edge FreeBSD, even though Ingo's development branch of CFS had lot's of improvements.
Member since:
2007-07-11
Oh really.. must have been great for the FreeBSD guys ego
Just take a look at the 6.2 scores, they are ridiculous. Linux has been ahead (performance wise) for so many years and now that FreeBSD finally (remember 7.0 isn't out yet) got something decent they cannot resist to.. well :-)
But please fanboys, keep the following in mind:
1. the latest development code of the scheduler (most of which was merged for 2.6.24) already had some improvements.
2. Ingo already committed a patch to improve performance further, see http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=...
3. Just read the FreeBSD-performance list, there are still cases where the "old" 4BSD scheduler performs better. Remember that CFS is still quite new. It'll match the performance of the old scheduler in time, let's see again what happens when 7.0 is out.