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>> >> + if (rq->scx.nr_running == 1) { >> + /* Account for idle runtime */ >> + if (!rq->nr_running) >> + dl_server_update_idle_time(rq, rq->curr, &rq->ext_server); >> + >> + /* Start dl_server if this is the first task being enqueued */ >> + dl_server_start(&rq->ext_server); >> + } > The following patch from Peter isn't upstream yet but SCX probably should do > something similar. Otherwise, the start/stop overhead can become pretty > expensive: > > https://lore.kernel.org/all/20250520094538.086709102@infradead.org/ Right. If it is Ok with you, we can do that after this patchset can be merged, that way we can use the 'dl_server_idle' addition to 'sched_dl_entity', from that patch as well. thanks, - Joel