Server（presto-0.207）启动涉及到的代码不是很多(这里只讨论大致的执行流程，不涉及具体的实现细节)，主要是关于Plugins的加载，读配置文件.properties，进行相应的操作。
首先，根据presto日志server.log定位服务启动的入口。
INFO main com.facebook.presto.server.PrestoServer ======== SERVER STARTED ========
启动类:presto-main/src/main/java/com/facebook/presto/server/PrestoServer.java
server启动的所有流程均在run()中实现：
首先，虚拟机参数相关验证，比如：是否JDK8+、JDK厂商：Oracle or OpenJDK、64-bit JVM版本、x86_64 on Mac OS，或者x86-64、amd64 on Linux系统，是否采用G1的垃圾回收器等。系统时间要求：必须是当前时间。
verifyJvmRequirements();
verifySystemTimeIsReasonable();
接着，创建不可变集合ImmutableList,传入一些启动模块，具体的实现细节，后续有需要再分析。
ImmutableList.Builder<Module> modules = ImmutableList.builder();
modules.add(
new NodeModule(),
new DiscoveryModule(),
new HttpServerModule(),
new JsonModule(),
new JaxrsModule(true),
new MBeanModule(),
new JmxModule(),
new JmxHttpModule(),
new LogJmxModule(),
new TraceTokenModule(),
new JsonEventModule(),
new HttpEventModule(),
new ServerSecurityModule(),
new AccessControlModule(),
new EventListenerModule(),
new ServerMainModule(sqlParserOptions),
new GracefulShutdownModule());
modules.addAll(getAdditionalModules());
//使用io.airlift.平台代码库构建的应用程序的入口点,并加载需要的module实例（包含一些启动默认参数）
Bootstrap app = new Bootstrap(modules.build());
关于启动的默认参数比较多，现截取一部分：
2018-08-24T10:54:27.769+0800 INFO main Bootstrap PROPERTY DEFAULT RUNTIME DESCRIPTION
2018-08-24T10:54:27.769+0800 INFO main Bootstrap event.max-output-stage-size 16MB 16MB
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.client.timeout 5.00m 5.00m
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.initial-hash-partitions 100 100
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query-manager.initialization-required-workers 1 1 Minimum number of workers that must be available before the cluster will accept queries
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query-manager.initialization-timeout 5.00m 5.00m After this time, the cluster will accept queries even if the minimum required workers are not available
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.max-concurrent-queries 1000 1000
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.max-history 100 100
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.max-length 1000000 1000000
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.max-queued-queries 5000 5000
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.min-expire-age 15.00m 15.00m
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.min-schedule-split-batch-size 100 100
2018-08-24T10:54:27.769+0800 INFO main Bootstrap query.execution-policy all-at-once all-at-once
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.manager-executor-pool-size 5 5
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.max-cpu-time 1000000000.00d 1000000000.00d
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.max-execution-time 100.00d 100.00d
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.max-run-time 100.00d 100.00d
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.remote-task.max-callback-threads 1000 1000
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.remote-task.max-error-duration 5.00m 5.00m
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.remote-task.min-error-duration 5.00m 5.00m
2018-08-24T10:54:27.770+0800 INFO main Bootstrap query.schedule-split-batch-size 1000 1000
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.client.timeout 2.00m 2.00m
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.http-response-threads 100 100
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.http-timeout-threads 3 3
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.info.max-age 15.00m 15.00m
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.info-update-interval 3.00s 3.00s Interval between updating task data
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.initial-splits-per-node 64 6
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.level-time-multiplier 2 2 Factor that determines the target scheduled time for a level relative to the next
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.max-drivers-per-task 2147483647 2147483647 Maximum number of drivers a task can run
2018-08-24T10:54:27.770+0800 INFO main Bootstrap task.max-index-memory 64MB 64MB
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.max-local-exchange-buffer-size 32MB 32MB
2018-08-24T10:54:27.771+0800 INFO main Bootstrap driver.max-page-partitioning-buffer-size 32MB 32MB
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.max-partial-aggregation-memory 16MB 16MB
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.max-worker-threads 64 6
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.min-drivers 128 12
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.min-drivers-per-task 3 3 Minimum number of drivers guaranteed to run per task given there is sufficient work to do
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.share-index-loading false false
2018-08-24T10:54:27.771+0800 INFO main Bootstrap sink.max-buffer-size 32MB 1GB
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.split-concurrency-adjustment-interval 100.00ms 100.00ms
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.status-refresh-max-wait 1.00s 1.00s
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.concurrency 16 16 Default number of local parallel jobs per worker
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.cpu-timer-enabled true true
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.task-notification-threads 5 5 Number of threads used for internal task event notifications
2018-08-24T10:54:27.771+0800 INFO main Bootstrap task.task-yield-threads 3 3 Number of threads used for setting yield signals
2018-08-24T10:54:27.772+0800 INFO main Bootstrap task.verbose-stats false false
开始加载plugins和配置文件
try {
Injector injector = app.strictConfig().initialize();
//生成PluginManager实例，载入/data0/presto/data/plugin目录下的.jar
injector.getInstance(PluginManager.class).loadPlugins();
//生成StaticCatalogStore实例，载入.properties配置文件
injector.getInstance(StaticCatalogStore.class).loadCatalogs();
// TODO: remove this huge hack
//更新UUID, ServiceAnnouncement
updateConnectorIds(
injector.getInstance(Announcer.class),
injector.getInstance(CatalogManager.class),
injector.getInstance(ServerConfig.class),
injector.getInstance(NodeSchedulerConfig.class));
//接口，无具体方法实现
injector.getInstance(SessionSupplier.class).loadConfigurationManager();
injector.getInstance(ResourceGroupManager.class).loadConfigurationManager();
//生成AccessControlManager实例，如果路径etc/下存在文件access-control.properties
//如果检查通过，或者不存在该文件，打印日志信息"-- Loaded system access control allow-all --"
injector.getInstance(AccessControlManager.class).loadSystemAccessControl();
//原理过程大致同上
injector.getInstance(PasswordAuthenticatorManager.class).loadPasswordAuthenticator();
injector.getInstance(EventListenerManager.class).loadConfiguredEventListener();
injector.getInstance(Announcer.class).start();
log.info("======== SERVER STARTED ========");
}
catch (Throwable e) {
log.error(e);
System.exit(1);
}
}
关于AccessControlManager.class下的loadSystemAccessControl()代码分析：
public void loadSystemAccessControl()
throws Exception
{
if (ACCESS_CONTROL_CONFIGURATION.exists()) {
Map<String, String> properties = new HashMap<>(loadProperties(ACCESS_CONTROL_CONFIGURATION));
String accessControlName = properties.remove(ACCESS_CONTROL_PROPERTY_NAME);
checkArgument(!isNullOrEmpty(accessControlName),
"Access control configuration %s does not contain %s", ACCESS_CONTROL_CONFIGURATION.getAbsoluteFile(), ACCESS_CONTROL_PROPERTY_NAME);
setSystemAccessControl(accessControlName, properties);
}
else {
setSystemAccessControl(AllowAllSystemAccessControl.NAME, ImmutableMap.of());
}
}
@VisibleForTesting
protected void setSystemAccessControl(String name, Map<String, String> properties)
{
requireNonNull(name, "name is null");
requireNonNull(properties, "properties is null");
checkState(systemAccessControlLoading.compareAndSet(false, true), "System access control already initialized");
log.info("-- Loading system access control --");
SystemAccessControlFactory systemAccessControlFactory = systemAccessControlFactories.get(name);
checkState(systemAccessControlFactory != null, "Access control %s is not registered", name);
SystemAccessControl systemAccessControl = systemAccessControlFactory.create(ImmutableMap.copyOf(properties));
this.systemAccessControl.set(systemAccessControl);
log.info("-- Loaded system access control %s --", name);
}
由于在集群中没有配置该文件，启动时默认allow-all，直接通过检查。后面两步的加载原理大致也是一样。运行到这里，就可以启动server了。
injector.getInstance(Announcer.class).start();
log.info("======== SERVER STARTED ========");
