History

Yuming Wang e00344edc1 [SPARK-29423][SS] lazily initialize StreamingQueryManager in SessionState ### What changes were proposed in this pull request? This PR makes `SessionState` lazily initialize `StreamingQueryManager` to avoid constructing `StreamingQueryManager` for each session when connecting to ThriftServer. ### Why are the changes needed? Reduce memory usage. ### Does this PR introduce any user-facing change? No. ### How was this patch tested? manual test 1. Start thriftserver: ``` build/sbt clean package -Phive -Phadoop-3.2 -Phive-thriftserver export SPARK_PREPEND_CLASSES=true sbin/start-thriftserver.sh ``` 2. Open a session: ``` bin/beeline -u jdbc:hive2://localhost:10000 ``` 3. Check `StreamingQueryManager` instance: ``` jcmd \| grep HiveThriftServer2 \| awk -F ' ' '{print $1}' \| xargs jmap -histo \| grep StreamingQueryManager ``` Before this PR: ``` [rootspark-3267648 spark]# jcmd \| grep HiveThriftServer2 \| awk -F ' ' '{print $1}' \| xargs jmap -histo \| grep StreamingQueryManager 1954: 2 96 org.apache.spark.sql.streaming.StreamingQueryManager ``` After this PR: ``` [rootspark-3267648 spark]# jcmd \| grep HiveThriftServer2 \| awk -F ' ' '{print $1}' \| xargs jmap -histo \| grep StreamingQueryManager [rootspark-3267648 spark]# ``` Closes #26089 from wangyum/SPARK-29423. Authored-by: Yuming Wang <yumwang@ebay.com> Signed-off-by: Dongjoon Hyun <dhyun@apple.com>		2019-10-15 21:08:15 -07:00
..
catalyst	[SPARK-24540][SQL] Support for multiple character delimiter in Spark CSV read	2019-10-15 15:44:51 -05:00
core	[SPARK-29423][SS] lazily initialize StreamingQueryManager in SessionState	2019-10-15 21:08:15 -07:00
hive	[SPARK-28885][SQL] Follow ANSI store assignment rules in table insertion by default	2019-10-15 10:41:37 -07:00
hive-thriftserver	[SPARK-28885][SQL] Follow ANSI store assignment rules in table insertion by default	2019-10-15 10:41:37 -07:00
create-docs.sh
gen-sql-markdown.py	[SPARK-27328][SQL] Add 'deprecated' in ExpressionDescription for extended usage and SQL doc	2019-04-09 13:49:42 +08:00
mkdocs.yml
README.md	[SPARK-28980][CORE][SQL][STREAMING][MLLIB] Remove most items deprecated in Spark 2.2.0 or earlier, for Spark 3	2019-09-09 10:19:40 -05:00

README.md

Spark SQL

This module provides support for executing relational queries expressed in either SQL or the DataFrame/Dataset API.

Spark SQL is broken up into four subprojects:

Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
Execution (sql/core) - A query planner / execution engine for translating Catalyst's logical query plans into Spark RDDs. This component also includes a new public interface, SQLContext, that allows users to execute SQL or LINQ statements against existing RDDs and Parquet files.
Hive Support (sql/hive) - Includes extensions that allow users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allow users to run queries that include Hive UDFs, UDAFs, and UDTFs.
HiveServer and CLI support (sql/hive-thriftserver) - Includes support for the SQL CLI (bin/spark-sql) and a HiveServer2 (for JDBC/ODBC) compatible server.

Running ./sql/create-docs.sh generates SQL documentation for built-in functions under sql/site.