Getting exception from Hystrix

问题

I am using hystrix for spring boot project but getting timeout exception.

Please find below controller code for details

@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)
}

While testing with more calls like 1500 hits in 5 min then getting timeout exception. While checking logs then find below logs

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]

Can someone please let me know how to solve this issue?

回答1:

You need to add hystrix property execution.isolation.semaphore.maxConcurrentRequests and set it to a higher number (200). The default value of execution.isolation.semaphore.maxConcurrentRequests is "10" so the method getData() will be allowed to be executed in parallel for not more than 10 times.

Similarly you need to add fallback.isolation.semaphore.maxConcurrentRequests and set it to 200 for your fall back method.

    @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() {
    
    }

来源：https://stackoverflow.com/questions/64390516/getting-exception-from-hystrix

标签

java

spring-boot

hystrix