Category : hystrix

Error 1 2017-03-28 10:04:47.438 ERROR 1035 — [InstanceMonitor] c.n.t.monitor.instance.InstanceMonitor : Could not initiate connection to host, giving up: [{“timestamp”:1490666687435,”status”:503,”error”:”Service Unavailable”,”message”:”MaxConcurrentConnections reached: 5″,”path”:”/hystrix.stream”}] ~/.m2/repository/com/netflix/hystrix/hystrix-metrics-event-stream/1.5.6/hystrix-metrics-event-stream-1.5.6-sources.jar! /com/netflix/hystrix/contrib/requests/stream/HystrixRequestEventsSseServlet.java public class HystrixRequestEventsSseServlet extends HystrixSampleSseServlet { private static final long serialVersionUID = 6389353893099737870L; /* used to track number of connections and throttle */ private static AtomicInteger concurrentConnections = new AtomicInteger(0); private ..

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Order During the pressure test, an exception occurred: “could not be queried for execution and no fallback available.” and “rejected command because three-pool query size is at rejection threshold.” Hystrix exception com.netflix.hystrix.exception.HystrixRuntimeException: xxx#xxx(String,String) could not be queued for execution and no fallback available. at com.netflix.hystrix.AbstractCommand$22.call(AbstractCommand.java:805) at com.netflix.hystrix.AbstractCommand$22.call(AbstractCommand.java:790) at rx.internal.operators.OperatorOnErrorResumeNextViaFunction$4.onError(OperatorOnErrorResumeNextViaFunction.java:140) at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onError(OnSubscribeDoOnEach.java:87) at com.netflix.hystrix.AbstractCommand$DeprecatedOnFallbackHookApplication$1.onError(AbstractCommand.java:1451) ..

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Order This article mainly studies the HystrixCommands of spring cloud netflix. maven <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> <version>2.0.0.RELEASE</version> </dependency> This component encapsulates hystrix, and 2.0.0.RELEASE fully supports Reactor’s Reactive Streams. spring-cloud-starter-netflix-hystrix/pom.xml spring-cloud-starter-netflix-hystrix-2.0.0.RELEASE.jar! /META-INF/maven/org.springframework.cloud/spring-cloud-starter-netflix-hystrix/pom.xml <project xmlns=”http://maven.apache.org/POM/4.0.0″ xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd”> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix</artifactId> <version>2.0.0.RELEASE</version> </parent> <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> <name>Spring Cloud Starter Netflix Hystrix</name> <description>Spring Cloud Starter Netflix Hystrix</description> <url>https://projects.spring.io/spring-cloud</url> <organization> ..

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Order This article mainly studies the spring cloud’s HystrixAutoConfiguration. HystrixAutoConfiguration spring-cloud-netflix-core-2.0.0.RELEASE-sources.jar! /org/springframework/cloud/netflix/hystrix/HystrixAutoConfiguration.java /** * Auto configuration for Hystrix. * * @author Christian Dupuis * @author Dave Syer */ @Configuration @ConditionalOnClass({ Hystrix.class, HealthIndicator.class }) @AutoConfigureAfter({ HealthIndicatorAutoConfiguration.class }) public class HystrixAutoConfiguration { @Bean @ConditionalOnEnabledHealthIndicator(“hystrix”) public HystrixHealthIndicator hystrixHealthIndicator() { return new HystrixHealthIndicator(); } @Bean @ConditionalOnProperty(value = “management.metrics.hystrix.enabled”, matchIfMissing ..

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Order This article mainly studies the Hystrixcircuitbreakerconfiguration of spring cloud. HystrixCircuitBreakerConfiguration spring-cloud-netflix-core-2.0.0.RELEASE-sources.jar! /org/springframework/cloud/netflix/hystrix/HystrixCircuitBreakerConfiguration.java @Configuration public class HystrixCircuitBreakerConfiguration { @Bean public HystrixCommandAspect hystrixCommandAspect() { return new HystrixCommandAspect(); } @Bean public HystrixShutdownHook hystrixShutdownHook() { return new HystrixShutdownHook(); } @Bean public HasFeatures hystrixFeature() { return HasFeatures.namedFeatures(new NamedFeature(“Hystrix”, HystrixCommandAspect.class)); } //FIXME: 2.0.0 /*@Configuration @ConditionalOnProperty(value = “hystrix.metrics.enabled”, matchIfMissing = true) ..

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Order This article mainly studies HystrixThreadPool HystrixThreadPool hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/HystrixThreadPool.java /** * ThreadPool used to executed {@link HystrixCommand#run()} on separate threads when configured to do so with {@link HystrixCommandProperties#executionIsolationStrategy()}. * <p> * Typically each {@link HystrixCommandGroupKey} has its own thread-pool so that any one group of commands can not starve others from being able to run. ..

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Order This article mainly studies the timeout processing of hystrix. HystrixObservableTimeoutOperator hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/AbstractCommand.java private static class HystrixObservableTimeoutOperator<R> implements Operator<R, R> { final AbstractCommand<R> originalCommand; public HystrixObservableTimeoutOperator(final AbstractCommand<R> originalCommand) { this.originalCommand = originalCommand; } @Override public Subscriber<? super R> call(final Subscriber<? super R> child) { final CompositeSubscription s = new CompositeSubscription(); // if the child unsubscribes ..

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Order This article mainly studies HystrixCircuitBreaker Flow Chart HystrixCircuitBreaker hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/HystrixCircuitBreaker.java /** * Circuit-breaker logic that is hooked into {@link HystrixCommand} execution and will stop allowing executions if failures have gone past the defined threshold. * <p> * The default (and only) implementation will then allow a single retry after a defined sleepWindow until the ..

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Order This paper mainly studies HystrixPlugins HystrixPlugins hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/strategy/HystrixPlugins.java /** * Registry for plugin implementations that allows global override and handles the retrieval of correct implementation based on order of precedence: * <ol> * <li>plugin registered globally via <code>register</code> methods in this class</li> * <li>plugin registered and retrieved using the resolved {@link HystrixDynamicProperties} (usually Archaius, ..

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Order This article mainly studies the HystrixEventNotifier HystrixEventNotifier /** * Abstract EventNotifier that allows receiving notifications for different events with default implementations. * <p> * See {@link HystrixPlugins} or the Hystrix GitHub Wiki for information on configuring plugins: <a * href=”https://github.com/Netflix/Hystrix/wiki/Plugins”>https://github.com/Netflix/Hystrix/wiki/Plugins</a>. * <p> * <b>Note on thread-safety and performance</b> * <p> * A single implementation ..

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Order This article mainly studies the HystrixConcurrencyStrategy HystrixConcurrencyStrategy hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/strategy/concurrency/HystrixConcurrencyStrategy.java /** * Abstract class for defining different behavior or implementations for concurrency related aspects of the system with default implementations. * <p> * For example, every {@link Callable} executed by {@link HystrixCommand} will call {@link #wrapCallable(Callable)} to give a chance for custom implementations to decorate ..

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Order This article mainly studies HystrixMetricsPublisher HystrixMetricsPublisher hystrix-core-1.5.12-sources.jar! /com/netflix/hystrix/strategy/metrics/HystrixMetricsPublisher.java /** * Abstract class with default implementations of Factory methods for creating “Metrics Publisher” instances for getting metrics and other related data * exposed, published or otherwise retrievable by external systems such as Servo (https://github.com/Netflix/servo) * for monitoring and statistical purposes. * <p> * See {@link ..

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