Messages in this thread | | | Subject | Re: [PATCH v3 3/7] sched: throttle cfs_rq entities which exceed their local quota | From | Peter Zijlstra <> | Date | Thu, 14 Oct 2010 11:12:22 +0200 |
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On Wed, 2010-10-13 at 15:34 +0900, KAMEZAWA Hiroyuki wrote: > cpu.share and bandwidth control can't be used simultaneously or... > is this fair ? I'm not familiar with scheduler but this allows boost this tg. > Could you add a brief documentaion of a spec/feature. in the next post ?
Like explained, shares control the proportional distribution of time between groups, bandwidth puts a limit on how much time a group can take. It can cause a group to receive less than its fair share, but never more.
There is, however, a problem with all this, and that is that all this explicit idling of tasks can lead to a form of priority inversion. Regular preemptive scheduling already suffers from this, but explicitly idling tasks exacerbates the situation.
You basically get to add the longest induced idle time to all your lock hold times.
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