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Con Kolivas Returns, With a Desktop-Oriented Linux Scheduler

myvirtualid writes "Con Kolivas has done what he swore never to do: returned to the Linux kernel and written a new — and, according to him — waaay better scheduler for the desktop environment. In fact, BFS appears to outperform existing schedulers right up until one hits a 16-CPU machine, at which point he guesses performance would degrade somewhat. According to Kolivas, BFS 'was designed to be forward looking only, make the most of lower spec machines, and not scale to massive hardware. i.e. [sic] it is a desktop orientated scheduler, with extremely low latencies for excellent interactivity by design rather than 'calculated,' with rigid fairness, nice priority distribution and extreme scalability within normal load levels.'"

4 of 333 comments (clear)

  1. BFS is the Brain Fuck Scheduler. by Anonymous Coward · · Score: 5, Interesting

    Why would the summary omit this precious bit of information?

  2. great news by amn108 · · Score: 5, Interesting

    Great news :-) Now, will the kernel people with Mr. Torvalds at their head, restart the whole debate on pluggable schedulers. Since his scheduler, as he says, degrades beyond 16 CPUs, better options already exists for servers where I am guessing CFS is used. So, he may be back, but the road ahead is still as steep?

  3. Glory! by CAIMLAS · · Score: 5, Interesting

    May I be the first to say "amen"? I've been very dissatisfied with the 2.6 kernel and its schedulers on the desktop, CFS in particular. CFS seems entirely braindead for desktop use compared to the older schedulers in 2.4 and yes, even 2.2.

    A desktop machine needs to be, first and foremost, responsive. If it isn't, it's comparable to the cursor freezing and input taking several seconds to appear: on today's hardware, one might start to think "hey, did it freeze on me?" - completely unacceptable.

    Maybe it can be chalked up to the non-priority of X and video at the kernel level; I don't know. Whatever it is, it used to be better, on very pathetic (133MHz) hardware, while doing a lot more (and when such hardware was not all that powerful anymore, as well).

    My question is: is it in the kernel tree yet? Is this that 2.6.31 scheduler change I heard about earlier yesterday, or is it something Completely Different?

    Oh yeah, and which other scheduler's, if any, did this guy write?

    --
    ~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
    1. Re:Glory! by kav2k · · Score: 5, Interesting

      Citing the FAQ:

      Are you looking at getting this into mainline?

      LOL.

      No really, are you?

      LOL.

      Really really, are you?

      No. They would be crazy to use this scheduler anyway since it won't scale to
      their 4096 cpu machines. The only way is to rewrite it to work that way, or
      to have more than one scheduler in the kernel. I don't want to do the former,
      and mainline doesn't want to do the latter. Besides, apparently I'm a bad
      maintainer, which makes sense since for some reason I seem to want to have
      a career, a life, raise a family with kids and have hobbies, all of which
      have nothing to do with linux.