Java parallelStream run task always wait a long time, why? - forkjoinpool

Question

I use parallelStream to execute backgroud task in Spring #Async annotation. but the task always blocked then stop. the core code is:
#Async
public void task() {
List<ConfigSymbol> symbols = SymbolUtils.getSaasOpenSymbol();
symbols .parallelStream().forEach(symbol->{
//execute task. 1 minute per loop
}
}
I catch the thread stack to diagnosis the problem. but can not find reason.
why the ForkJoinTask status is waiting .
"SimpleAsyncTaskExecutor-1609" #1777 prio=5 os_prio=0 tid=0x00007fb968006800 nid=0x6f5 in Object.wait() [0x00007fba2d119000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.util.concurrent.ForkJoinTask.externalAwaitDone(ForkJoinTask.java:334)
- locked <0x00000006428a0a38> (a java.util.stream.ForEachOps$ForEachTask)
at java.util.concurrent.ForkJoinTask.doInvoke(ForkJoinTask.java:405)
at java.util.concurrent.ForkJoinTask.invoke(ForkJoinTask.java:734)
at java.util.stream.ForEachOps$ForEachOp.evaluateParallel(ForEachOps.java:159)
at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateParallel(ForEachOps.java:173)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:233)
at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:485)
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:650)
at com.chainup.stats.service.impl.StatsSymbolRateServiceImpl.getCalculationBTCExchangeRate(StatsSymbolRateServiceImpl.java:141)
at com.chainup.stats.service.impl.StatsSymbolRateServiceImpl.runThreadExchangeRate(StatsSymbolRateServiceImpl.java:67)
at com.chainup.stats.action.StatAct.insertStatsSymbolRate(StatAct.java:442)
at com.chainup.stats.action.StatAct$$FastClassBySpringCGLIB$$74ae31d4.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:769)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:88)
at org.springframework.cloud.sleuth.instrument.async.TraceAsyncAspect.traceBackgroundThread(TraceAsyncAspect.java:66)
at sun.reflect.GeneratedMethodAccessor277.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:88)
at com.chainup.stats.interceptor.StatsJobInterceptor.around(StatsJobInterceptor.java:99)
at sun.reflect.GeneratedMethodAccessor273.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:95)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
at org.springframework.aop.interceptor.AsyncExecutionInterceptor.lambda$invoke$0(AsyncExecutionInterceptor.java:115)
at org.springframework.aop.interceptor.AsyncExecutionInterceptor$$Lambda$790/775437217.call(Unknown Source)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.springframework.cloud.sleuth.instrument.async.TraceRunnable.run(TraceRunnable.java:65)
at java.lang.Thread.run(Thread.java:748)