SpringCloud-Hystrix 报 could not acquire a semaphore for execution

今天SpringCloud-Hystrix 并发调用报could not acquire a semaphore for execution，配置以下设置，完美解决

hystrix:
  command:
    default:
      execution:
        isolation:
          strategy: SEMAPHORE
          thread:
            timeoutInMilliseconds:  120000
          semaphore:
            maxConcurrentRequests: 1000
      circuitBreaker:
        sleepWindowInMilliseconds:  5000