Re: [PATCH v7 2/5] cpuset: Add cpuset.sched_load_balance to v2

On Wed, May 02, 2018 at 09:47:00AM -0400, Waiman Long wrote:

quoted

I've read half of the next patch that adds the isolation thing. And
while that kludges around the whole root cgorup is magic thing, it
doesn't help if you move the above scenario on level down:


	R
     /    \
   A        B
          /   \
        C       D


R: cpus=0-7, load_balance=0
A: cpus=0-1, load_balance=1
B: cpus=2-7, load_balance=0
C: cpus=2-3, load_balance=1
D: cpus=4-7, load_balance=1


Also, I feel we should strive to have a minimal amount of tasks that
cannot be moved out of the root group; the current set is far too large.

What exactly is the use case you have in mind with loading balancing
disabled in B, but enabled in C and D? We would like to support some
sensible use cases, but not every possible combinations.

Suppose A is your system group, and C and D are individual RT workloads
or something.

Or suppose B has siblings and each group at that level is a delegate to
a particular user/container. And the user/container in B happens to need
2 partitioned VMs or whatever.

The idea is the same in all the examples, you want to allow
sub-partitions.