phase phase#1 "并发发起 50 个独立 worker" @27:1
phase phase#2 "汇总 50 个 worker 的产物" @41:1
lane actor#1 name-head="worker-" @33:5 families=fanout#1
lane actor#2 "summarizer" @42:23
region seq#1 seq
region fanout#1 fanout parent=seq#1 @32:3 label="from"
step ask#1 ask "ask" label-head="worker-" @35:8 lane=actor#1 phase=phase#1 region=fanout#1 maybe stack
step ask#2 ask "summarizer" @44:4 lane=actor#2 phase=phase#2 region=seq#1 always
edge ask#1 -> ask#2 data maybe exact
phase-edge phase#1 -> phase#2 data maybe
sink ask#2
