从Hystrix获取异常

Question

我正在使用hystrix进行spring boot项目，但是得到了超时异常。

有关详细信息，请参阅下面的控制器代码

@GetMapping("/getData")
@HystrixCommand(fallbackMethod = "getDataFallBack", commandProperties = { @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "60000"), @HystrixProperty(name = "execution.isolation.strategy", value = "SEMAPHORE") })
public ResponseEntity<Object> getData() {

}

/**
 * Fallback method for getData
 */
public ResponseEntity<Object> getDataFallBack(Throwable e) {
    LOGGER.info("In fallback method", e)
}

当测试更多的呼叫时，比如5分钟内1500次点击，然后得到超时异常。同时检查日志，然后找到下面的日志

java.lang.RuntimeException: could not acquire a semaphore for execution
    at com.netflix.hystrix.AbstractCommand.handleSemaphoreRejectionViaFallback(AbstractCommand.java:966) ~[hystrix-core-1.5.18.jar!/:1.5.18]
    at com.netflix.hystrix.AbstractCommand.applyHystrixSemantics(AbstractCommand.java:554) ~[hystrix-core-1.5.18.jar!/:1.5.18]
    at com.netflix.hystrix.AbstractCommand.access$200(AbstractCommand.java:60) ~[hystrix-core-1.5.18.jar!/:1.5.18]
    at com.netflix.hystrix.AbstractCommand$4.call(AbstractCommand.java:419) ~[hystrix-core-1.5.18.jar!/:1.5.18]
    at com.netflix.hystrix.AbstractCommand$4.call(AbstractCommand.java:413) ~[hystrix-core-1.5.18.jar!/:1.5.18]
    at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:46) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:35) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.Observable.unsafeSubscribe(Observable.java:10327) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.Observable.unsafeSubscribe(Observable.java:10327) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48) [rxjava-1.3.8.jar!/:1.3.8]
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30) [rxjava-1.3.8.jar!/:1.3.8]

有没有人可以告诉我如何解决这个问题？

Answer 1

您需要添加hystrix属性execution.isolation.semaphore.maxConcurrentRequests并将其设置为更高的数字(200)。execution.isolation.semaphore.maxConcurrentRequests的默认值是" 10“，因此允许getData()方法并行执行不超过10次。

同样，对于回退方法，您需要添加fallback.isolation.semaphore.maxConcurrentRequests并将其设置为200。

    @GetMapping("/getData")
    @HystrixCommand(fallbackMethod = "getDataFallBack", commandProperties = { @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "60000"), 
    @HystrixProperty(name = "execution.isolation.strategy", value = "SEMAPHORE"),@HystrixProperty(name = "execution.isolation.semaphore.maxConcurrentRequests", value = "200") })
    public ResponseEntity<Object> getData() {
    
    }