Linux Gets Completely Fair Scheduler

SchedFred writes "KernelTrap is reporting that CFS, Ingo Molnar's Completely Fair Scheduler, was just merged into the Linux kernel. The new CPU scheduler includes a pluggable framework that completely replaces Molnar's earlier O(1) scheduler, and is described to 'model an "ideal, precise multi-tasking CPU" on real hardware. CFS tries to run the task with the "gravest need" for more CPU time. So CFS always tries to split up CPU time between runnable tasks as close to "ideal multitasking hardware" as possible.' The new CPU scheduler should improve the desktop Linux experience, and will be part of the upcoming 2.6.23 kernel."

crap

[cachimaster]

just finished make xconfig;make from 2.6.22!

Equal opportunity, affirmative action scheduler

[EmbeddedJanitor]

For the really touchy-feely OS out there!

Re:Equal opportunity, affirmative action scheduler

[ArcherB]

For the really touchy-feely OS out there!
Does this mean all apps will play nice? [about.com]

Re:crap

[cachimaster]

Is not fair!

For the attention of karma whores

[SoVeryTired]

Karma Whores:

Steal your insightful comments from http://linux.slashdot.org/article.pl?sid=07/04/22/ 1335255 [slashdot.org]

Why...

[lawpoop]

Why does this sound like the title of a Monty Python Skit?

"Why isn't my process getting more CPU time?"

"Well, Sir, it's a Completely Fair Scheduler."

Isn't This Called Cron?

[Anonymous Coward]

I thought Linux used Cron as a scheduler ?

Re:Equal opportunity, affirmative action scheduler

[Lithdren]

No it just means programs wont crash other programs based purly on the programming langauge that was used to bring them into being. All languages were created equal.

Except Basic. Nobody likes basic.

Isnt this called Cron?

[TheVelvetFlamebait]

I thought Linux used Cron as a scheduler ?
 

Re:Equal opportunity, affirmative action scheduler

[Anonymous Coward]

It also means that tasks which were denied adequate runtime in the past will now be favored over current tasks, to make up for the prior unfairness. :)

Anyone with kids can tell you...

[s_p_oneil]

The only way to make it completely fair is to let one thread slice the time up, and let the other thread choose which slice it wants. ;-)

Re:Neato

[smartdreamer]

you'll feel a placebo effect.

Re:Equal opportunity, affirmative action scheduler

[Anonymous Coward]

Except Basic. Nobody likes basic.

goto hell you insensitive clod!

Completly fair = communist?

[smartdreamer]

So does Linux reached the computer's communist's holy grail?

Re:crap

[setagllib]

With desktop environments like GNOME taking up more CPU time per user than all Google servers combined, a strong scheduler is desirable to make it at least sort-of tolerable. Although really, switching to KDE is known to have a much stronger positive effect.

Cool-If Bush wrote operating systems.

[Anonymous Coward]

"I had always been impressed with Linux's scheduler. The fact that it is getting better, just makes me happy."

I like the "No task left behind" scheduler too.

hmmmm..........

[Sillygates]

What version of KDE are you running?

Re:Equal opportunity, affirmative action scheduler

[sharkey]

Affirmative preemption!

Re:Anyone with kids can tell you...

[Burdell]

Yeah, but then when you get three threads, it gets more complicated. Also, one indecisive thread, and everybody stands around and complains while the one tries to decide which slice to take.

It's Worse Than That

[grcumb]

A complete fair scheduler for geeks? I can just see it:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 user 16 0 1464 184 140 S 90.0 86.1 0:01.93 wank
2 user RT 0 0 0 0 S 10.0 13.9 0:00.00 porn
3 user 34 19 0 0 0 Z 0.0 0.0 0:00.00 work
4 user RT 0 0 0 0 Z 0.0 0.0 0:00.00 socialise
5 user 10 -5 0 0 0 Z 0.0 0.0 0:00.31 getadate

Re:Completly fair = communist?

[maino82]

in communist kernel, task schedules YOU!

Welfare scheduler

[jihadist]

Next up: equal time for processes that produce no tangible result. Soon Linux will run like the bloated bureaucratic nightmare that is the USA.

Ok, here's your Microsoft bash

[Weaselmancer]

You can download it here. [cygwin.com] Screenshots here. [khngai.com]

Re:Equal opportunity, affirmative action scheduler

[Aethedor]

You meant: 10 GOTO 666 666 PRINT you insensitive clod!

Re:Equal opportunity, affirmative action scheduler

[Andrzej Sawicki]

instead of psdoom we will now use psOMG_PONIES?

Fixed.

Re:Anyone with kids can tell you...

[complete loony]

Look, if you two threads can't learn to cooperate, neither of you will get a time slice.

Re:crap

[dam.capsule.org]

Fair enough.

Re:Neato

[BooleanLobster]

Hey, you're right! I feel it!

You mean for....

[EmbeddedJanitor]

the preemptively challenged.

Then there's the American Dream sheduler where you get priority if you work hard at it. You can't just inheret your priority like some rich child process.

Re:You mean for....

[Plutonite]

I long for the day when processes will no longer be judged by the digits of their pid, but by the niceness of their cycles!

Also, in Soviet Russia, nice tasks preempt YOU!

Re:AWESOME!!!!!!!!!!

[Anonymous Coward]

Maybe... but be nice, because chances are you work for one of us.

Re:Isnt this called Cron?

[bioglaze]

Yeah, and it performs better with Cron Kolivas patchset :-)

Of course..

[Ztream]

"Hello. My name is Ingo Molnar. You killed my task. Prepare to die."