Flink on yarn 实战和源码分析

版本：1.13.6

Flink on yarn 的3种模式的使用

yarn session 模式源码分析

yarn per-job模式源码分析

application模式源码分析

Flink on yarn 的3种模式的使用

Application Mode #

./bin/flink run-application -t yarn-application ./examples/streaming/TopSpeedWindowing.jar

Per-Job Mode #

./bin/flink run -t yarn-per-job --detached ./examples/streaming/TopSpeedWindowing.jar

Session Mode #

./bin/flink run -t yarn-session ./examples/streaming/TopSpeedWindowing.jar

注意：application 方式使用的action为 run-application，而 per-job session mode 都是 run -t。为什么不统一呢，官方没注意到？

yarn session 模式源码分析

以样例TopSpeedWindowing.jar为例，命令行提交命令为：

./bin/flink run -t yarn-session ./examples/streaming/TopSpeedWindowing.jar

根据bin/flink脚本中的入口类 org.apache.flink.client.cli.CliFrontend

1、找到bin/flink 提交脚本中看到启动类即程序的入口是： org.apache.flink.client.cli.CliFrontend

2、查看其中的main方法，执行的逻辑简单总结如下：

获取flink的conf目录的路径
根据conf路径，加载配置
封装命令行接口：按顺序Generic、Yarn、Default

/** Submits the job based on the arguments. */
public static void main(final String[] args) {
    EnvironmentInformation.logEnvironmentInfo(LOG, "Command Line Client", args);

    // 1. find the configuration directory
    final String configurationDirectory = getConfigurationDirectoryFromEnv();

    // 2. load the global configuration
    final Configuration configuration =
            GlobalConfiguration.loadConfiguration(configurationDirectory);

    // 3. load the custom command lines
    final List<CustomCommandLine> customCommandLines =
            loadCustomCommandLines(configuration, configurationDirectory);

    int retCode = 31;
    try {
        final CliFrontend cli = new CliFrontend(configuration, customCommandLines);

        SecurityUtils.install(new SecurityConfiguration(cli.configuration));
        retCode = SecurityUtils.getInstalledContext().runSecured(() -> cli.parseAndRun(args));
    } catch (Throwable t) {
        final Throwable strippedThrowable =
                ExceptionUtils.stripException(t, UndeclaredThrowableException.class);
        LOG.error("Fatal error while running command line interface.", strippedThrowable);
        strippedThrowable.printStackTrace();
    } finally {
        System.exit(retCode);
    }
}

parseAndRun 方法中根据命令行的第一个参数匹配action ,此模式参数为run ,所以 case ACTION_RUN:

/**
 * Parses the command line arguments and starts the requested action.
 *
 * @param args command line arguments of the client.
 * @return The return code of the program
 */
public int parseAndRun(String[] args) {

    // check for action
    if (args.length < 1) {
        CliFrontendParser.printHelp(customCommandLines);
        System.out.println("Please specify an action.");
        return 1;
    }

    // get action
    String action = args[0];

    // remove action from parameters
    final String[] params = Arrays.copyOfRange(args, 1, args.length);

    try {
        // do action
        switch (action) {
            case ACTION_RUN:
                run(params);
                return 0;
            case ACTION_RUN_APPLICATION:
                runApplication(params);
                return 0;
            case ACTION_LIST:
                list(params);
                return 0;
            case ACTION_INFO:
                info(params);
                return 0;
            case ACTION_CANCEL:
                cancel(params);
                return 0;
            case ACTION_STOP:
                stop(params);
                return 0;
            case ACTION_SAVEPOINT:
                savepoint(params);
                return 0;
            case "-h":
            case "--help":
                CliFrontendParser.printHelp(customCommandLines);
                return 0;
            case "-v":
            case "--version":
                String version = EnvironmentInformation.getVersion();
                String commitID = EnvironmentInformation.getRevisionInformation().commitId;
                System.out.print("Version: " + version);
                System.out.println(
                        commitID.equals(EnvironmentInformation.UNKNOWN)
                                ? ""
                                : ", Commit ID: " + commitID);
                return 0;
            default:
                System.out.printf("\"%s\" is not a valid action.\n", action);
                System.out.println();
                System.out.println(
                        "Valid actions are \"run\", \"run-application\", \"list\", \"info\", \"savepoint\", \"stop\", or \"cancel\".");
                System.out.println();
                System.out.println(
                        "Specify the version option (-v or --version) to print Flink version.");
                System.out.println();
                System.out.println(
                        "Specify the help option (-h or --help) to get help on the command.");
                return 1;
        }
    } catch (CliArgsException ce) {
        return handleArgException(ce);
    } catch (ProgramParametrizationException ppe) {
        return handleParametrizationException(ppe);
    } catch (ProgramMissingJobException pmje) {
        return handleMissingJobException();
    } catch (Exception e) {
        return handleError(e);
    }
}

/**
 * Executions the run action.
 *
 * @param args Command line arguments for the run action.
 */
protected void run(String[] args) throws Exception {
    LOG.info("Running 'run' command.");
    //获取run的动作，默认的配置项
    final Options commandOptions = CliFrontendParser.getRunCommandOptions();
    //根据用户指定的配置项，进行解析 例如-t -p -c等
    final CommandLine commandLine = getCommandLine(commandOptions, args, true);

    // evaluate help flag,只要参数中包含help 打印后结束
    if (commandLine.hasOption(HELP_OPTION.getOpt())) {
        CliFrontendParser.printHelpForRun(customCommandLines);
        return;
    }

    final CustomCommandLine activeCommandLine =
            validateAndGetActiveCommandLine(checkNotNull(commandLine));

    final ProgramOptions programOptions = ProgramOptions.create(commandLine);

    //获取 用户的jar包和其他依赖
    final List<URL> jobJars = getJobJarAndDependencies(programOptions);

    //获取有效配置：HA的id、Target（session、per-job）、JobManager内存、TaskManager内存、每个TM的slot数
    final Configuration effectiveConfiguration =
            getEffectiveConfiguration(activeCommandLine, commandLine, programOptions, jobJars);

    LOG.debug("Effective executor configuration: {}", effectiveConfiguration);
    // PackagedProgram 类很关键，
    try (PackagedProgram program = getPackagedProgram(programOptions, effectiveConfiguration)) {
        // 执行程序
        executeProgram(effectiveConfiguration, program);
    }
}

yarn per-job模式源码分析

以样例TopSpeedWindowing.jar为例，命令行提交命令为：

./bin/flink run -t yarn-per-job --detached ./examples/streaming/TopSpeedWindowing.jar

application模式源码分析

Flink 1.11 版本引入了 Application 模式。

应用模式是唯一一个main方法不在客户端上执行的。其他两种模式都要在本地管理依赖资源，运行main方法然后生成JobGraph并提交到集群，不仅增加了网络传输的压力，还消耗了客户端大量的CPU资源。为了解决这个问题，应用模式先把用户jar包等资源提交到资源平台，然后创建Flink集群并自动在服务器上运行应用main方法。在main方法中可以通过execute或executeAysnc提交任务并记录提交作业id，作业执行完毕后，集群自动关闭。因此这种模式可以跟Per Job一样做到单任务的资源隔离，同时也可以解决客户端的计算瓶颈问题。

另外，应用模式支持提交多个作业，作业的顺序依赖于启动顺序。如果使用的是execute()会阻塞按顺序执行；如果使用的是executeAysnc，各个任务可能会乱序执行。

bin目录下 flink脚本内容，可以看到入口类为 org.apache.flink.client.cli.CliFrontend

#!/usr/bin/env bash
################################################################################
#  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.
################################################################################

target="$0"
# For the case, the executable has been directly symlinked, figure out
# the correct bin path by following its symlink up to an upper bound.
# Note: we can't use the readlink utility here if we want to be POSIX
# compatible.
iteration=0
while [ -L "$target" ]; do
    if [ "$iteration" -gt 100 ]; then
        echo "Cannot resolve path: You have a cyclic symlink in $target."
        break
    fi
    ls=`ls -ld -- "$target"`
    target=`expr "$ls" : '.* -> \(.*\)$'`
    iteration=$((iteration + 1))
done

# Convert relative path to absolute path
bin=`dirname "$target"`

# get flink config
. "$bin"/config.sh

if [ "$FLINK_IDENT_STRING" = "" ]; then
        FLINK_IDENT_STRING="$USER"
fi

CC_CLASSPATH=`constructFlinkClassPath`

log=$FLINK_LOG_DIR/flink-$FLINK_IDENT_STRING-client-$HOSTNAME.log
log_setting=(-Dlog.file="$log" -Dlog4j.configuration=file:"$FLINK_CONF_DIR"/log4j-cli.properties -Dlog4j.configurationFile=file:"$FLINK_CONF_DIR"/log4j-cli.properties -Dlogback.configurationFile=file:"$FLINK_CONF_DIR"/logback.xml)

# Add Client-specific JVM options
FLINK_ENV_JAVA_OPTS="${FLINK_ENV_JAVA_OPTS} ${FLINK_ENV_JAVA_OPTS_CLI}"

# Add HADOOP_CLASSPATH to allow the usage of Hadoop file systems
exec "${JAVA_RUN}" $JVM_ARGS $FLINK_ENV_JAVA_OPTS "${log_setting[@]}" -classpath "`manglePathList "$CC_CLASSPATH:$INTERNAL_HADOOP_CLASSPATHS"`" org.apache.flink.client.cli.CliFrontend "$@"

使用application方式提交样例作业