docs/building-spark.md - spark - Git at Google

 ---
 layout: global
 title: Building Spark
 redirect_from: "building-with-maven.html"
 license: |
   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

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 * This will become a table of contents (this text will be scraped).
 {:toc}

 # Building Apache Spark

 ## Apache Maven

 The Maven-based build is the build of reference for Apache Spark.
 Building Spark using Maven requires Maven 3.9.9 and Java 17/21.
 Spark requires Scala 2.13; support for Scala 2.12 was removed in Spark 4.0.0.

 ### Setting up Maven's Memory Usage

 You'll need to configure Maven to use more memory than usual by setting `MAVEN_OPTS`:

 ```sh
 export MAVEN_OPTS="-Xss64m -Xmx2g -XX:ReservedCodeCacheSize=1g"
 ```

 (The `ReservedCodeCacheSize` setting is optional but recommended.)
 If you don't add these parameters to `MAVEN_OPTS`, you may see errors and warnings like the following:

     [INFO] Compiling 203 Scala sources and 9 Java sources to /Users/me/Development/spark/core/target/scala-{{site.SCALA_BINARY_VERSION}}/classes...
     [ERROR] Java heap space -> [Help 1]

 You can fix these problems by setting the `MAVEN_OPTS` variable as discussed before.

 **Note:**

 * If using `build/mvn` with no `MAVEN_OPTS` set, the script will automatically add the above options to the `MAVEN_OPTS` environment variable.
 * The `test` phase of the Spark build will automatically add these options to `MAVEN_OPTS`, even when not using `build/mvn`.

 ### build/mvn

 Spark now comes packaged with a self-contained Maven installation to ease building and deployment of Spark from source located under the `build/` directory. This script will automatically download and setup all necessary build requirements ([Maven](https://maven.apache.org/), [Scala](https://www.scala-lang.org/)) locally within the `build/` directory itself. It honors any `mvn` binary if present already, however, will pull down its own copy of Scala regardless to ensure proper version requirements are met. `build/mvn` execution acts as a pass through to the `mvn` call allowing easy transition from previous build methods. As an example, one can build a version of Spark as follows:

     ./build/mvn -DskipTests clean package

 Other build examples can be found below.

 ## Building a Runnable Distribution

 To create a Spark distribution like those distributed by the
 [Spark Downloads](https://spark.apache.org/downloads.html) page, and that is laid out so as
 to be runnable, use `./dev/make-distribution.sh` in the project root directory. By default,
 it uses Maven as building tool, and can be configured with Maven profile settings and so on
 like the direct Maven build. Example:

     ./dev/make-distribution.sh --name custom-spark --pip --r --tgz -Psparkr -Phive -Phive-thriftserver -Pyarn -Pkubernetes

 This will build Spark distribution along with Python pip and R packages.

 To switch to SBT (experimental), use `--sbt-enabled`. Example:

     ./dev/make-distribution.sh --name custom-spark --pip --r --tgz --sbt-enabled -Psparkr -Phive -Phive-thriftserver -Pyarn -Pkubernetes

 For more information on usage, run `./dev/make-distribution.sh --help`

 ## Specifying the Hadoop Version and Enabling YARN

 You can enable the `yarn` profile and specify the exact version of Hadoop to compile against through the `hadoop.version` property.

 Example:

     ./build/mvn -Pyarn -Dhadoop.version=3.4.1 -DskipTests clean package

 ## Building With Hive and JDBC Support

 To enable Hive integration for Spark SQL along with its JDBC server and CLI,
 add the `-Phive` and `-Phive-thriftserver` profiles to your existing build options.
 By default Spark will build with Hive 2.3.10.

     # With Hive 2.3.10 support
     ./build/mvn -Pyarn -Phive -Phive-thriftserver -DskipTests clean package

 ## Packaging without Hadoop Dependencies for YARN

 The assembly directory produced by `mvn package` will, by default, include all of Spark's
 dependencies, including Hadoop and some of its ecosystem projects. On YARN deployments, this
 causes multiple versions of these to appear on executor classpaths: the version packaged in
 the Spark assembly and the version on each node, included with `yarn.application.classpath`.
 The `hadoop-provided` profile builds the assembly without including Hadoop-ecosystem projects,
 like ZooKeeper and Hadoop itself.

 ## Building with Kubernetes support

     ./build/mvn -Pkubernetes -DskipTests clean package

 ## Building submodules individually

 It's possible to build Spark submodules using the `mvn -pl` option.

 For instance, you can build the Spark Streaming module using:

     ./build/mvn -pl :spark-streaming_{{site.SCALA_BINARY_VERSION}} clean install

 where `spark-streaming_{{site.SCALA_BINARY_VERSION}}` is the `artifactId` as defined in `streaming/pom.xml` file.

 ## Building with JVM Profile support

     ./build/mvn -Pjvm-profiler -DskipTests clean package

 **Note:** The `jvm-profiler` profile builds the assembly without including the dependency `ap-loader`,
 you can download it manually from maven central repo and use it together with `spark-profiler_{{site.SCALA_BINARY_VERSION}}`.

 ## Continuous Compilation

 We use the scala-maven-plugin which supports incremental and continuous compilation. E.g.

     ./build/mvn scala:cc

 should run continuous compilation (i.e. wait for changes). However, this has not been tested
 extensively. A couple of gotchas to note:

 * it only scans the paths `src/main` and `src/test` (see
 [docs](https://davidb.github.io/scala-maven-plugin/example_cc.html)), so it will only work
 from within certain submodules that have that structure.

 * you'll typically need to run `mvn install` from the project root for compilation within
 specific submodules to work; this is because submodules that depend on other submodules do so via
 the `spark-parent` module).

 Thus, the full flow for running continuous-compilation of the `core` submodule may look more like:

     $ ./build/mvn install
     $ cd core
     $ ../build/mvn scala:cc

 ## Building with SBT

 Maven is the official build tool recommended for packaging Spark, and is the *build of reference*.
 But SBT is supported for day-to-day development since it can provide much faster iterative
 compilation. More advanced developers may wish to use SBT.

 The SBT build is derived from the Maven POM files, and so the same Maven profiles and variables
 can be set to control the SBT build. For example:

     ./build/sbt package

 To avoid the overhead of launching sbt each time you need to re-compile, you can launch sbt
 in interactive mode by running `build/sbt`, and then run all build commands at the command
 prompt.

 ### Setting up SBT's Memory Usage
 Configure the JVM options for SBT in `.jvmopts` at the project root, for example:

     -Xmx2g
     -XX:ReservedCodeCacheSize=1g

 For the meanings of these two options, please carefully read the [Setting up Maven's Memory Usage section](https://spark.apache.org/docs/latest/building-spark.html#setting-up-mavens-memory-usage).

 ## Speeding up Compilation

 Developers who compile Spark frequently may want to speed up compilation; e.g., by avoiding re-compilation of the
 assembly JAR (for developers who build with SBT).  For more information about how to do this, refer to the
 [Useful Developer Tools page](https://spark.apache.org/developer-tools.html#reducing-build-times).

 ## Encrypted Filesystems

 When building on an encrypted filesystem (if your home directory is encrypted, for example), then the Spark build might fail with a "Filename too long" error. As a workaround, add the following in the configuration args of the `scala-maven-plugin` in the project `pom.xml`:

 ```xml
 <arg>-Xmax-classfile-name</arg>
 <arg>128</arg>
 ```

 and in `project/SparkBuild.scala` add:

 ```scala
 scalacOptions in Compile ++= Seq("-Xmax-classfile-name", "128"),
 ```

 to the `sharedSettings` val. See also [this PR](https://github.com/apache/spark/pull/2883/files) if you are unsure of where to add these lines.

 ## IntelliJ IDEA or Eclipse

 For help in setting up IntelliJ IDEA or Eclipse for Spark development, and troubleshooting, refer to the
 [Useful Developer Tools page](https://spark.apache.org/developer-tools.html).


 # Running Tests

 Tests are run by default via the [ScalaTest Maven plugin](http://www.scalatest.org/user_guide/using_the_scalatest_maven_plugin).
 Note that tests should not be run as root or an admin user.

 The following is an example of a command to run the tests:

     ./build/mvn test

 ## Testing with SBT

 The following is an example of a command to run the tests:

     ./build/sbt test

 ## Running Individual Tests

 For information about how to run individual tests, refer to the
 [Useful Developer Tools page](https://spark.apache.org/developer-tools.html#running-individual-tests).

 ## PySpark pip installable

 If you are building Spark for use in a Python environment and you wish to pip install it, you will first need to build the Spark JARs as described above. Then you can construct an sdist package suitable for setup.py and pip installable package.

     cd python; python packaging/classic/setup.py sdist

 **Note:** Due to packaging requirements you can not directly pip install from the Python directory, rather you must first build the sdist package as described above.

 Alternatively, you can also run `make-distribution.sh` with the `--pip` option.

 ## PySpark Tests with Maven or SBT

 If you are building PySpark and wish to run the PySpark tests you will need to build Spark with Hive support.

     ./build/mvn -DskipTests clean package -Phive
     ./python/run-tests

 If you are building PySpark with SBT and wish to run the PySpark tests, you will need to build Spark with Hive support and also build the test components:

     ./build/sbt -Phive clean package
     ./build/sbt test:compile
     ./python/run-tests

 The run-tests script also can be limited to a specific Python version or a specific module

     ./python/run-tests --python-executables=python --modules=pyspark-sql

 ## Running R Tests (deprecated)

 To run the SparkR tests you will need to install the [knitr](https://cran.r-project.org/package=knitr), [rmarkdown](https://cran.r-project.org/package=rmarkdown), [testthat](https://cran.r-project.org/package=testthat), [e1071](https://cran.r-project.org/package=e1071) and [survival](https://cran.r-project.org/package=survival) packages first:

     Rscript -e "install.packages(c('knitr', 'rmarkdown', 'devtools', 'testthat', 'e1071', 'survival'), repos='https://cloud.r-project.org/')"

 You can run just the SparkR tests using the command:

     ./R/run-tests.sh

 ## Running Docker-based Integration Test Suites

 In order to run Docker integration tests, you have to install the `docker` engine on your box.
 The instructions for installation can be found at [the Docker site](https://docs.docker.com/engine/installation/).
 Once installed, the `docker` service needs to be started, if not already running.
 On Linux, this can be done by `sudo service docker start`.

     ./build/mvn install -DskipTests
     ./build/mvn test -Pdocker-integration-tests -pl :spark-docker-integration-tests_{{site.SCALA_BINARY_VERSION}}

 or

     ./build/sbt -Pdocker-integration-tests docker-integration-tests/test

 <!---
 ## Change Scala Version

 When other versions of Scala like 2.13 are supported, it will be possible to build for that version.
 Change the major Scala version using (e.g. 2.13):

     ./dev/change-scala-version.sh 2.13

 Enable the profile (e.g. 2.13):

     # For Maven
     ./build/mvn -Pscala-2.13 compile

     # For sbt
     ./build/sbt -Pscala-2.13 compile
 -->

 # Building and testing on an IPv6-only environment

 Use Apache Spark GitBox URL because GitHub doesn't support IPv6 yet.

     https://gitbox.apache.org/repos/asf/spark.git

 To build and run tests on IPv6-only environment, the following configurations are required.

 ```sh
 export SPARK_LOCAL_HOSTNAME="your-IPv6-address" # e.g. '[2600:1700:232e:3de0:...]'
 export DEFAULT_ARTIFACT_REPOSITORY=https://ipv6.repo1.maven.org/maven2/
 export MAVEN_OPTS="-Djava.net.preferIPv6Addresses=true"
 export SBT_OPTS="-Djava.net.preferIPv6Addresses=true"
 export SERIAL_SBT_TESTS=1
 ```

 # Building with a user-defined `protoc`

 When the user cannot use the official `protoc` binary files to build the `core` module in the compilation environment, for example, compiling `core` module on CentOS 6 or CentOS 7 which the default `glibc` version is less than 2.14, we can try to compile and test by specifying the user-defined `protoc` binary files as follows:

 ```bash
 export SPARK_PROTOC_EXEC_PATH=/path-to-protoc-exe
 ./build/mvn -Puser-defined-protoc -DskipDefaultProtoc clean package
 ```

 or

 ```bash
 export SPARK_PROTOC_EXEC_PATH=/path-to-protoc-exe
 ./build/sbt -Puser-defined-protoc clean package
 ```

 The user-defined `protoc` binary files can be produced in the user's compilation environment by source code compilation, for compilation steps, please refer to [protobuf](https://github.com/protocolbuffers/protobuf).
	---
	layout: global
	title: Building Spark
	redirect_from: "building-with-maven.html"
	license: \|
	Licensed to the Apache Software Foundation (ASF) under one or more
	contributor license agreements. See the NOTICE file distributed with
	this work for additional information regarding copyright ownership.
	The ASF licenses this file to You under the Apache License, Version 2.0
	(the "License"); you may not use this file except in compliance with
	the License. You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	---

	* This will become a table of contents (this text will be scraped).
	{:toc}

	# Building Apache Spark

	## Apache Maven

	The Maven-based build is the build of reference for Apache Spark.
	Building Spark using Maven requires Maven 3.9.9 and Java 17/21.
	Spark requires Scala 2.13; support for Scala 2.12 was removed in Spark 4.0.0.

	### Setting up Maven's Memory Usage

	You'll need to configure Maven to use more memory than usual by setting `MAVEN_OPTS`:

	```sh
	export MAVEN_OPTS="-Xss64m -Xmx2g -XX:ReservedCodeCacheSize=1g"
	```

	(The `ReservedCodeCacheSize` setting is optional but recommended.)
	If you don't add these parameters to `MAVEN_OPTS`, you may see errors and warnings like the following:

	[INFO] Compiling 203 Scala sources and 9 Java sources to /Users/me/Development/spark/core/target/scala-{{site.SCALA_BINARY_VERSION}}/classes...
	[ERROR] Java heap space -> [Help 1]

	You can fix these problems by setting the `MAVEN_OPTS` variable as discussed before.

	Note:

	* If using `build/mvn` with no `MAVEN_OPTS` set, the script will automatically add the above options to the `MAVEN_OPTS` environment variable.
	* The `test` phase of the Spark build will automatically add these options to `MAVEN_OPTS`, even when not using `build/mvn`.

	### build/mvn

	Spark now comes packaged with a self-contained Maven installation to ease building and deployment of Spark from source located under the `build/` directory. This script will automatically download and setup all necessary build requirements ([Maven](https://maven.apache.org/), [Scala](https://www.scala-lang.org/)) locally within the `build/` directory itself. It honors any `mvn` binary if present already, however, will pull down its own copy of Scala regardless to ensure proper version requirements are met. `build/mvn` execution acts as a pass through to the `mvn` call allowing easy transition from previous build methods. As an example, one can build a version of Spark as follows:

	./build/mvn -DskipTests clean package

	Other build examples can be found below.

	## Building a Runnable Distribution

	To create a Spark distribution like those distributed by the
	[Spark Downloads](https://spark.apache.org/downloads.html) page, and that is laid out so as
	to be runnable, use `./dev/make-distribution.sh` in the project root directory. By default,
	it uses Maven as building tool, and can be configured with Maven profile settings and so on
	like the direct Maven build. Example:

	./dev/make-distribution.sh --name custom-spark --pip --r --tgz -Psparkr -Phive -Phive-thriftserver -Pyarn -Pkubernetes

	This will build Spark distribution along with Python pip and R packages.

	To switch to SBT (experimental), use `--sbt-enabled`. Example:

	./dev/make-distribution.sh --name custom-spark --pip --r --tgz --sbt-enabled -Psparkr -Phive -Phive-thriftserver -Pyarn -Pkubernetes

	For more information on usage, run `./dev/make-distribution.sh --help`

	## Specifying the Hadoop Version and Enabling YARN

	You can enable the `yarn` profile and specify the exact version of Hadoop to compile against through the `hadoop.version` property.

	Example:

	./build/mvn -Pyarn -Dhadoop.version=3.4.1 -DskipTests clean package

	## Building With Hive and JDBC Support

	To enable Hive integration for Spark SQL along with its JDBC server and CLI,
	add the `-Phive` and `-Phive-thriftserver` profiles to your existing build options.
	By default Spark will build with Hive 2.3.10.

	# With Hive 2.3.10 support
	./build/mvn -Pyarn -Phive -Phive-thriftserver -DskipTests clean package

	## Packaging without Hadoop Dependencies for YARN

	The assembly directory produced by `mvn package` will, by default, include all of Spark's
	dependencies, including Hadoop and some of its ecosystem projects. On YARN deployments, this
	causes multiple versions of these to appear on executor classpaths: the version packaged in
	the Spark assembly and the version on each node, included with `yarn.application.classpath`.
	The `hadoop-provided` profile builds the assembly without including Hadoop-ecosystem projects,
	like ZooKeeper and Hadoop itself.

	## Building with Kubernetes support

	./build/mvn -Pkubernetes -DskipTests clean package

	## Building submodules individually

	It's possible to build Spark submodules using the `mvn -pl` option.

	For instance, you can build the Spark Streaming module using:

	./build/mvn -pl :spark-streaming_{{site.SCALA_BINARY_VERSION}} clean install

	where `spark-streaming_{{site.SCALA_BINARY_VERSION}}` is the `artifactId` as defined in `streaming/pom.xml` file.

	## Building with JVM Profile support

	./build/mvn -Pjvm-profiler -DskipTests clean package

	Note: The `jvm-profiler` profile builds the assembly without including the dependency `ap-loader`,
	you can download it manually from maven central repo and use it together with `spark-profiler_{{site.SCALA_BINARY_VERSION}}`.

	## Continuous Compilation

	We use the scala-maven-plugin which supports incremental and continuous compilation. E.g.

	./build/mvn scala:cc

	should run continuous compilation (i.e. wait for changes). However, this has not been tested
	extensively. A couple of gotchas to note:

	* it only scans the paths `src/main` and `src/test` (see
	[docs](https://davidb.github.io/scala-maven-plugin/example_cc.html)), so it will only work
	from within certain submodules that have that structure.

	* you'll typically need to run `mvn install` from the project root for compilation within
	specific submodules to work; this is because submodules that depend on other submodules do so via
	the `spark-parent` module).

	Thus, the full flow for running continuous-compilation of the `core` submodule may look more like:

	$ ./build/mvn install
	$ cd core
	$ ../build/mvn scala:cc

	## Building with SBT

	Maven is the official build tool recommended for packaging Spark, and is the build of reference.
	But SBT is supported for day-to-day development since it can provide much faster iterative
	compilation. More advanced developers may wish to use SBT.

	The SBT build is derived from the Maven POM files, and so the same Maven profiles and variables
	can be set to control the SBT build. For example:

	./build/sbt package

	To avoid the overhead of launching sbt each time you need to re-compile, you can launch sbt
	in interactive mode by running `build/sbt`, and then run all build commands at the command
	prompt.

	### Setting up SBT's Memory Usage
	Configure the JVM options for SBT in `.jvmopts` at the project root, for example:

	-Xmx2g
	-XX:ReservedCodeCacheSize=1g

	For the meanings of these two options, please carefully read the [Setting up Maven's Memory Usage section](https://spark.apache.org/docs/latest/building-spark.html#setting-up-mavens-memory-usage).

	## Speeding up Compilation

	Developers who compile Spark frequently may want to speed up compilation; e.g., by avoiding re-compilation of the
	assembly JAR (for developers who build with SBT). For more information about how to do this, refer to the
	[Useful Developer Tools page](https://spark.apache.org/developer-tools.html#reducing-build-times).

	## Encrypted Filesystems

	When building on an encrypted filesystem (if your home directory is encrypted, for example), then the Spark build might fail with a "Filename too long" error. As a workaround, add the following in the configuration args of the `scala-maven-plugin` in the project `pom.xml`:

	```xml
	<arg>-Xmax-classfile-name</arg>
	<arg>128</arg>
	```

	and in `project/SparkBuild.scala` add:

	```scala
	scalacOptions in Compile ++= Seq("-Xmax-classfile-name", "128"),
	```

	to the `sharedSettings` val. See also [this PR](https://github.com/apache/spark/pull/2883/files) if you are unsure of where to add these lines.

	## IntelliJ IDEA or Eclipse

	For help in setting up IntelliJ IDEA or Eclipse for Spark development, and troubleshooting, refer to the
	[Useful Developer Tools page](https://spark.apache.org/developer-tools.html).


	# Running Tests

	Tests are run by default via the [ScalaTest Maven plugin](http://www.scalatest.org/user_guide/using_the_scalatest_maven_plugin).
	Note that tests should not be run as root or an admin user.

	The following is an example of a command to run the tests:

	./build/mvn test

	## Testing with SBT

	The following is an example of a command to run the tests:

	./build/sbt test

	## Running Individual Tests

	For information about how to run individual tests, refer to the
	[Useful Developer Tools page](https://spark.apache.org/developer-tools.html#running-individual-tests).

	## PySpark pip installable

	If you are building Spark for use in a Python environment and you wish to pip install it, you will first need to build the Spark JARs as described above. Then you can construct an sdist package suitable for setup.py and pip installable package.

	cd python; python packaging/classic/setup.py sdist

	Note: Due to packaging requirements you can not directly pip install from the Python directory, rather you must first build the sdist package as described above.

	Alternatively, you can also run `make-distribution.sh` with the `--pip` option.

	## PySpark Tests with Maven or SBT

	If you are building PySpark and wish to run the PySpark tests you will need to build Spark with Hive support.

	./build/mvn -DskipTests clean package -Phive
	./python/run-tests

	If you are building PySpark with SBT and wish to run the PySpark tests, you will need to build Spark with Hive support and also build the test components:

	./build/sbt -Phive clean package
	./build/sbt test:compile
	./python/run-tests

	The run-tests script also can be limited to a specific Python version or a specific module

	./python/run-tests --python-executables=python --modules=pyspark-sql

	## Running R Tests (deprecated)

	To run the SparkR tests you will need to install the [knitr](https://cran.r-project.org/package=knitr), [rmarkdown](https://cran.r-project.org/package=rmarkdown), [testthat](https://cran.r-project.org/package=testthat), [e1071](https://cran.r-project.org/package=e1071) and [survival](https://cran.r-project.org/package=survival) packages first:

	Rscript -e "install.packages(c('knitr', 'rmarkdown', 'devtools', 'testthat', 'e1071', 'survival'), repos='https://cloud.r-project.org/')"

	You can run just the SparkR tests using the command:

	./R/run-tests.sh

	## Running Docker-based Integration Test Suites

	In order to run Docker integration tests, you have to install the `docker` engine on your box.
	The instructions for installation can be found at [the Docker site](https://docs.docker.com/engine/installation/).
	Once installed, the `docker` service needs to be started, if not already running.
	On Linux, this can be done by `sudo service docker start`.

	./build/mvn install -DskipTests
	./build/mvn test -Pdocker-integration-tests -pl :spark-docker-integration-tests_{{site.SCALA_BINARY_VERSION}}

	or

	./build/sbt -Pdocker-integration-tests docker-integration-tests/test

	<!---
	## Change Scala Version

	When other versions of Scala like 2.13 are supported, it will be possible to build for that version.
	Change the major Scala version using (e.g. 2.13):

	./dev/change-scala-version.sh 2.13

	Enable the profile (e.g. 2.13):

	# For Maven
	./build/mvn -Pscala-2.13 compile

	# For sbt
	./build/sbt -Pscala-2.13 compile
	-->

	# Building and testing on an IPv6-only environment

	Use Apache Spark GitBox URL because GitHub doesn't support IPv6 yet.

	https://gitbox.apache.org/repos/asf/spark.git

	To build and run tests on IPv6-only environment, the following configurations are required.

	```sh
	export SPARK_LOCAL_HOSTNAME="your-IPv6-address" # e.g. '[2600:1700:232e:3de0:...]'
	export DEFAULT_ARTIFACT_REPOSITORY=https://ipv6.repo1.maven.org/maven2/
	export MAVEN_OPTS="-Djava.net.preferIPv6Addresses=true"
	export SBT_OPTS="-Djava.net.preferIPv6Addresses=true"
	export SERIAL_SBT_TESTS=1
	```

	# Building with a user-defined `protoc`

	When the user cannot use the official `protoc` binary files to build the `core` module in the compilation environment, for example, compiling `core` module on CentOS 6 or CentOS 7 which the default `glibc` version is less than 2.14, we can try to compile and test by specifying the user-defined `protoc` binary files as follows:

	```bash
	export SPARK_PROTOC_EXEC_PATH=/path-to-protoc-exe
	./build/mvn -Puser-defined-protoc -DskipDefaultProtoc clean package
	```

	or

	```bash
	export SPARK_PROTOC_EXEC_PATH=/path-to-protoc-exe
	./build/sbt -Puser-defined-protoc clean package
	```

	The user-defined `protoc` binary files can be produced in the user's compilation environment by source code compilation, for compilation steps, please refer to [protobuf](https://github.com/protocolbuffers/protobuf).