Hive VW isolation auto-scaling
The Hive Virtual Warehouse in Cloudera Data Warehouse (CDW) Public Cloud bases its
auto-scaling on the size of data scanned for a query. Queries that scan amounts of data
that exceed the
hive.query.isolation.scan.size.threshold setting use the query
isolation method of auto-scaling.
- If the query does not exceed the hive.query.isolation.scan.size.threshold, concurrency scaling occurs.
- If the query does exceed the hive.query.isolation.scan.size.threshold, query isolation scaling occurs.
HiveServer generates a preliminary query execution plan.
- You run a single ETL-type query.
- The query exceeds the hive.query.isolation.scan.size.threshold.
Otherwise, the concurrency method of auto-scaling is used.
The following diagram shows the isolation method of auto-scaling:
The variable-sized, ephemeral executor groups for ETL terminate after the query completes.