Kurt Deschler created IMPALA-12533: -------------------------------------- Summary: Support row materialization outside of fetch lock Key: IMPALA-12533 URL: https://issues.apache.org/jira/browse/IMPALA-12533 Project: IMPALA Issue Type: Improvement Components: Backend Reporter: Kurt Deschler Assignee: Kurt Deschler
The HS2 protocol supports multi-stream fetch which allows thrift serialization, transport, and deserialization to be done in parallel using multiple connections from the client. However, query result fetch, root expression evaluation, and thrift result materialization are serialized under the fetch lock. Initial testing of multi-stream fetch showed that thrift result materialization and expression evaluation constitute significant processing and limit scaling with multiple streams. While it it would be difficult to support multiple streams to the root sink, raw data can be copied out of the root sink and materialized outside of the fetch lock without adding much complexity. -- This message was sent by Atlassian Jira (v8.20.10#820010)