scx_nest: Reset schedulings when a task is dispatched #18
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In scx_nest, we currently count the number of times that a core is scheduled for compaction before we eventually just eagerly compact the core. The idea is that the core could thrash between being scheduled and then "de-scheduled" for compaction if there are a couple of tasks that are bouncing between cores in the primary nest often enough to kick them out of being compacted. We're currently resetting schedulings when a core is eagerly compacted, but to be precise we should probably also reset the count when a core consumes a task from the fallback DSQ, at this indicates that the system is overcommitted and that we likely won't benefit from compacting the primary nest. Signed-off-by: David Vernet <void@manifault.com>
htejun
approved these changes
Dec 8, 2023
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In scx_nest, we currently count the number of times that a core is scheduled for compaction before we eventually just eagerly compact the core. The idea is that the core could thrash between being scheduled and then "de-scheduled" for compaction if there are a couple of tasks that are bouncing between cores in the primary nest often enough to kick them out of being compacted.
We're currently resetting schedulings when a core is eagerly compacted, but to be precise we should probably also reset the count when a core consumes a task from the fallback DSQ, at this indicates that the system is overcommitted and that we likely won't benefit from compacting the primary nest.