be9a804f2e
# What changes were proposed in this pull request? 1. Start HiveThriftServer2. 2. Connect to thriftserver through beeline. 3. Close the beeline. 4. repeat step2 and step 3 for many times. we found there are many directories never be dropped under the path `hive.exec.local.scratchdir` and `hive.exec.scratchdir`, as we know the scratchdir has been added to deleteOnExit when it be created. So it means that the cache size of FileSystem `deleteOnExit` will keep increasing until JVM terminated. In addition, we use `jmap -histo:live [PID]` to printout the size of objects in HiveThriftServer2 Process, we can find the object `org.apache.spark.sql.hive.client.HiveClientImpl` and `org.apache.hadoop.hive.ql.session.SessionState` keep increasing even though we closed all the beeline connections, which may caused the leak of Memory. # How was this patch tested? manual tests This PR follw-up the https://github.com/apache/spark/pull/19989 Author: zuotingbing <zuo.tingbing9@zte.com.cn> Closes #20029 from zuotingbing/SPARK-22793. |
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catalyst | ||
core | ||
hive | ||
hive-thriftserver | ||
create-docs.sh | ||
gen-sql-markdown.py | ||
mkdocs.yml | ||
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 an extension of SQLContext called HiveContext that allows users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allows 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
.