Investigating The OS Workers DMV

Ewald Cress continues his DMV internals series:

wait_started_ms_ticks is set in SOS_Task::PreWait(), i.e. just before actually suspending, and again cleared in SOS_Task::PostWait(). For more about the choreography of suspending, see here.

wait_resumed_ms_ticks is set in SOS_Scheduler::PrepareWorkerForResume(), itself called by the mysteriously named but highly popular SOS_Scheduler::ResumeNoCuzz().

start_quantum is set for the Resuming and InstantResuming case within SOS_Scheduler::TaskTransition(), called by SOS_Scheduler::Switch() as the worker is woken up after a wait.

Ewald intends this post as an extension of the official documentation, so it’s best to read that documentation in conjunction with this post.

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