Separate preparation stages can fall behind

Fresh-data pathQuery-ready dataNewlywrittenOrderedraw dataOrdered pre-aggregatedQuery engineQuerycomputeFreshdatacontinuouslyFastanswerscontinuouslyClickHouse Cloud · Fresh-data pathQuery-ready dataIngestserviceOrderedraw dataOrdered pre-aggregatedQuery engineQuerycomputeFreshdatacontinuouslyFastanswerscontinuouslyIn memoryOrderPre-aggregate + orderOther systems · Fresh-data pathQuery-ready dataDataingestionOrderedraw dataPre-aggregateddataQuery engineQuerycomputeFreshdatacontinuouslyFastanswerscontinuouslyAsync orderingAsync pre-aggrefresh Ordering work Caught up Pre-aggregation work Caught up Scan work Less Aggregate work Less Latency & query cost ↓ Lower Background merges preserve order + combine summaries Batch 8Batch 7Batch 2

Architecture explanation adapted from deck slide 32g. Preparation phases and work levels are qualitative. Independent preparation cycles use the native deck motion.