Linux: DeskOpt, "Completely Unfair Scheduling"
,----[ Quote ]
| "Completely fair scheduling is [a] really good thing, but if you want the
| best performance for certain applications you need to tune up some things,"
| explained Michal Piotrowski in his announcement for the fifth version of his
| DeskOpt daemon.
`----
http://kerneltrap.org/Linux/DeskOpt_Completely_Unfair_Scheduling
The biggest usability bug in Windows
,----[ Quote ]
| To that lofty end, I'm going to step down from my dramatic soliloquy and
| ask "Why in the name of all that is holy does it have to take so long to
| start Windows?"
`----
http://www.dexodesign.com/2007/09/biggest-usability-bug-in-windows.html
Related:
[Vista scheduler is broken]
,----[ Quote ]
| Critical optimizations such as zero-copy aside, there is no excusable reason
| why processing IP packets should so damagingly affect the system.
|
| [...]
|
| Putting aside the larger problem for the moment, there are several issues
| with this solution. It prioritizes multimedia playback over networking
| performance, which, as the resulting clamor has shown, is not everyone's
| personal policy preference. It is almost assuredly a layering violation. It
| picks a fixed and hard-coded packet limit (ten per millisecond), which won't
| scale across different hardware—think significantly faster processors or
| substantially slower networking drivers. It ignores the commonality of GigE.
| And, finally, the solution is complicated, as the convoluted description and
| resulting bugs in the implementation demonstrate.
`----
http://blogbeebe.blogspot.com/2007/08/robert-love-backs-up-my-very-simple.html
Linux: Discussing the Really Fair Scheduler
,----[ Quote ]
| Ingo Molnar reviewed Roman Zippel's Really Fair Scheduler code, suggesting
| that much of the work was similar to that which was being done by Peter
| Zijlstra
`----
http://kerneltrap.org/Linux/Discussing_the_Really_Fair_Scheduler
Linux: The Really Fair Scheduler
,----[ Quote ]
| He offered a mathematical overview of how his new scheduler works, included
| some benchmarks, and reflected back to earlier discussions on the lkml...
`----
http://kerneltrap.org/Linux/The_Really_Fair_Scheduler
Linux: The Original Process Scheduler
,----[ Quote ]
| In a June of 1992 posting to the linux-activists mailing list, Linus Torvalds
| described the original Linux scheduler noting, "the scheduler in linux is
| pretty simple, but does a reasonably good job at giving good IO response
| while not being too unfair against cpu-bound processes."
|
| [...]
|
| * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and
| * make semaphores SMP safe
| * 1998-11-19 Implemented schedule_timeout() and related stuff
| * by Andrea Arcangeli
| * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar:
| * hybrid priority-list and round-robin design with
| * an array-switch method of distributing timeslices
| * and per-CPU runqueues. Cleanups and useful suggestions
| * by Davide Libenzi, preemptible kernel bits by Robert Love.
| * 2003-09-03 Interactivity tuning by Con Kolivas.
| * 2004-04-02 Scheduler domains code by Nick Piggin
| * 2007-04-15 Work begun on replacing all interactivity tuning with a
| * fair scheduling design by Con Kolivas.
| * 2007-05-05 Load balancing (smp-nice) and other improvements
| * by Peter Williams
| * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith
| * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri
`----
http://kerneltrap.org/node/14191
Linux: Tuning CFS
,----[ Quote ]
| Nick Piggin used 'git bisect' to track a lmbench regression to the main CFS
| commit, leading to an interesting discussion between Nick and Ingo Molnar.
`----
http://kerneltrap.org/node/14055
Linux: CFS and 3D Gaming
,----[ Quote ]
| Some of the concerns expressed about the Completely Fair Scheduler were
| reports that it might not handle 3D games as well as the SD scheduler.
`----
http://kerneltrap.org/node/14023
CFS scheduler to appear in Linux kernel 2.6.23
,----[ Quote ]
| And also credit where credit's due, Con Kolivas was the first one to
| prove via RSDL/SD that 'fair scheduling' is possible and that it
| results in better desktop scheduling.
`----
http://www.linuxinsight.com/cfs-scheduler-to-appear-in-linux-kernel-2.6.23.html
Linux: Linus On CFS vs SD
,----[ Quote ]
| "People who think SD was 'perfect' were simply ignoring reality," Linus
| Torvalds began in a succinct explanation as to why he chose the CFS scheduler
| written by Ingo Molnar instead of the SD scheduler written by Con Kolivas.
`----
http://kerneltrap.org/node/14008
|
|
