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: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.
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
>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:
2006-07-15
Well, well according to Kris Kennaway (FreeBSD developers), CFS is completely fair to FreeBSD - well done indeed *g*
http://people.freebsd.org/~kris/scaling/7.0%20Preview.pdf">S... , Page 19