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    SubjectRe: [PATCH 2/5] cgroup/cpuset: Add new cpus.partition type with no load balancing
    On Thu, Jun 03, 2021 at 05:24:13PM -0400, Waiman Long wrote:
    > Cpuset v1 uses the sched_load_balance control file to determine if load
    > balancing should be enabled. Cpuset v2 gets rid of sched_load_balance
    > as its use may require disabling load balancing at cgroup root.
    >
    > For workloads that require very low latency like DPDK, the latency
    > jitters caused by periodic load balancing may exceed the desired
    > latency limit.
    >
    > When cpuset v2 is in use, the only way to avoid this latency cost is to
    > use the "isolcpus=" kernel boot option to isolate a set of CPUs. After
    > the kernel boot, however, there is no way to add or remove CPUs from
    > this isolated set. For workloads that are more dynamic in nature, that
    > means users have to provision enough CPUs for the worst case situation
    > resulting in excess idle CPUs.
    >
    > To address this issue for cpuset v2, a new cpuset.cpus.partition type
    > "root-nolb" is added which allows the creation of a cpuset partition with
    > no load balancing. This will allow system administrators to dynamically
    > adjust the size of the no load balancing partition to the current need
    > of the workload without rebooting the system.

    I'm confused, why do you need this? Just create a parition for each cpu.

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