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posts/2020-04-27-cfs-group/index #4

Open utterances-bot opened 7 months ago

utterances-bot commented 7 months ago

Linux CFS and task group – Mechpen

https://mechpen.github.io/posts/2020-04-27-cfs-group/index.html

LinuxKernel99 commented 7 months ago

Hey, nice article

i have a question, you mentioned that delta is being multiplied by weight/1024 my confusion here is the weight for higher priority tasks is higher than lower priority tasks, which leads into larger increment into the vruntime, but it should be the opposite where lower priority tasks should receives smaller increments ?

LinuxKernel99 commented 7 months ago

if i am not wrong it should be delta_exec * NICE_0_LOAD / curr->load.weight

LinuxKernel99 commented 7 months ago

https://elixir.bootlin.com/linux/v2.6.36.4/source/kernel/sched.c#L1316

mechpen commented 7 months ago

You are right. I fixed the equation. Thank you!

wagler commented 7 months ago

Thanks for the article. However, the CFS was recently replaced by the EEVDF scheduler in the kernel. Could you make another post about that one? Seems like it inherits lots of the data structures and some of the concepts of the CFS.