BlockHound does not detect Thread.sleep() in Spring/Kotlin/WebFlux setup

Question

BlockHound does not detect Thread.sleep() in Spring/Kotlin/WebFlux setup

faustuzas opened this issue 3 years ago · comments

Faustas Butkus commented 3 years ago

Expected Behavior

BlockHound should detect that a blocking call was made in controller method

Actual Behavior

Thread.sleep() works as normal blocking the thread.

Steps to Reproduce

import kotlinx.coroutines.debug.CoroutinesBlockHoundIntegration
import org.springframework.boot.autoconfigure.SpringBootApplication
import org.springframework.boot.runApplication
import org.springframework.web.bind.annotation.GetMapping
import org.springframework.web.bind.annotation.RequestMapping
import org.springframework.web.bind.annotation.RestController
import reactor.blockhound.BlockHound

@SpringBootApplication
class SampleApplication

@RestController
@RequestMapping("/samples")
class SampleController {

	@GetMapping
	fun sampleGet(): String {
		Thread.sleep(4000)
		return "hello there"
	}
}

fun main(args: Array<String>) {
	BlockHound.builder()
		.with(CoroutinesBlockHoundIntegration())
		.install()

	runApplication<SampleApplication>(*args)
}

Your Environment

build.gradle.kts

import org.jetbrains.kotlin.gradle.tasks.KotlinCompile

plugins {
	id("org.springframework.boot") version "2.4.3"
	id("io.spring.dependency-management") version "1.0.11.RELEASE"
	kotlin("jvm") version "1.4.30"
	kotlin("plugin.spring") version "1.4.30"
}

group = "sample"
version = "0.0.1-SNAPSHOT"
java.sourceCompatibility = JavaVersion.VERSION_11

repositories {
	mavenCentral()
}

dependencies {

	implementation("org.springframework.boot:spring-boot-starter-webflux")
	implementation("io.projectreactor.kotlin:reactor-kotlin-extensions")

	// Kotlin related
	implementation("org.jetbrains.kotlin:kotlin-reflect")
	implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
	implementation("org.jetbrains.kotlinx:kotlinx-coroutines-reactor")
	implementation("com.fasterxml.jackson.module:jackson-module-kotlin")

	implementation("io.projectreactor.tools:blockhound:1.0.4.RELEASE")
	implementation("org.jetbrains.kotlinx:kotlinx-coroutines-debug:1.4.0-M1")

	testImplementation("org.springframework.boot:spring-boot-starter-test")
	testImplementation("io.projectreactor:reactor-test")
}

tasks.withType<KotlinCompile> {
	kotlinOptions {
		freeCompilerArgs = listOf("-Xjsr305=strict")
		jvmTarget = "11"
	}
}

tasks.withType<Test> {
	useJUnitPlatform()
}

JVM version (java -version):

openjdk version "11.0.2" 2019-01-15
OpenJDK Runtime Environment 18.9 (build 11.0.2+9)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.2+9, mixed mode)

OS and version (eg uname -a):

Darwin macbook.local 19.6.0 Darwin Kernel Version 19.6.0: Thu Jun 18 20:49:00 PDT 2020; root:xnu-6153.141.1~1/RELEASE_X86_64 x86_64

Rui Pinto · Answer 1 · Sat Mar 20 2021 02:43:49 GMT+0800 (China Standard Time)

You should use install(SomeIntegration()) instead of the builder because builder ignores the built-in integrations since it skips the SPI mechanism.

Quoting the builder java doc:

Creates a completely new BlockHound.Builder that *does not* have any integration applied. 
Use it only if you want to ignore the built-in SPI mechanism (see install(BlockHoundIntegration...)).

In your case BlockHound.install() should be enough (the reactor/netty and coroutine integration should be loaded automatically)

Faustas Butkus · Answer 2 · Sat Mar 20 2021 15:56:27 GMT+0800 (China Standard Time)

Simply installing the BlockHound like this
BlockHound.install() produces an exception when handling simple controller method

@GetMapping
fun sampleGet(): String {
    return "hello there"
}

Stack trace:

09:54:05.446 [reactor-http-nio-3] ERROR o.s.b.a.w.r.e.AbstractErrorWebExceptionHandler - [e31a6a78-1]  500 Server Error for HTTP GET "/samples"
reactor.blockhound.BlockingOperationError: Blocking call! java.io.RandomAccessFile#readBytes
	at java.base/java.io.RandomAccessFile.readBytes(RandomAccessFile.java)
	Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
	|_ checkpoint ⇢ HTTP GET "/samples" [ExceptionHandlingWebHandler]
Stack trace:
		at java.base/java.io.RandomAccessFile.readBytes(RandomAccessFile.java)
		at java.base/java.io.RandomAccessFile.read(RandomAccessFile.java:406)
		at java.base/java.io.RandomAccessFile.readFully(RandomAccessFile.java:470)
		at java.base/java.util.zip.ZipFile$Source.readFullyAt(ZipFile.java:1298)
		at java.base/java.util.zip.ZipFile$ZipFileInputStream.initDataOffset(ZipFile.java:997)
		at java.base/java.util.zip.ZipFile$ZipFileInputStream.read(ZipFile.java:1012)
		at java.base/java.util.zip.ZipFile$ZipFileInflaterInputStream.fill(ZipFile.java:467)
		at java.base/java.util.zip.InflaterInputStream.read(InflaterInputStream.java:159)
		at java.base/java.util.zip.InflaterInputStream.read(InflaterInputStream.java:123)
		at java.base/java.io.FilterInputStream.read(FilterInputStream.java:83)
		at java.base/java.io.DataInputStream.readInt(DataInputStream.java:392)
		at kotlin.reflect.jvm.internal.impl.metadata.builtins.BuiltInsBinaryVersion$Companion.readFrom(BuiltInsBinaryVersion.kt:29)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.builtins.BuiltInsPackageFragmentImpl$Companion.create(BuiltInsPackageFragmentImpl.kt:38)
		at kotlin.reflect.jvm.internal.impl.builtins.jvm.JvmBuiltInsPackageFragmentProvider.findPackage(JvmBuiltInsPackageFragmentProvider.kt:61)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.AbstractDeserializedPackageFragmentProvider$fragments$1.invoke(AbstractDeserializedPackageFragmentProvider.kt:35)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.AbstractDeserializedPackageFragmentProvider$fragments$1.invoke(AbstractDeserializedPackageFragmentProvider.kt:34)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$MapBasedMemoizedFunction.invoke(LockBasedStorageManager.java:578)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.AbstractDeserializedPackageFragmentProvider.collectPackageFragments(AbstractDeserializedPackageFragmentProvider.kt:43)
		at kotlin.reflect.jvm.internal.impl.descriptors.PackageFragmentProviderKt.collectPackageFragmentsOptimizedIfPossible(PackageFragmentProvider.kt:50)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.CompositePackageFragmentProvider.collectPackageFragments(CompositePackageFragmentProvider.kt:47)
		at kotlin.reflect.jvm.internal.impl.descriptors.PackageFragmentProviderKt.collectPackageFragmentsOptimizedIfPossible(PackageFragmentProvider.kt:50)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.CompositePackageFragmentProvider.collectPackageFragments(CompositePackageFragmentProvider.kt:47)
		at kotlin.reflect.jvm.internal.impl.descriptors.PackageFragmentProviderKt.collectPackageFragmentsOptimizedIfPossible(PackageFragmentProvider.kt:50)
		at kotlin.reflect.jvm.internal.impl.descriptors.PackageFragmentProviderKt.packageFragments(PackageFragmentProvider.kt:41)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.LazyPackageViewDescriptorImpl$fragments$2.invoke(LazyPackageViewDescriptorImpl.kt:38)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.LazyPackageViewDescriptorImpl$fragments$2.invoke(LazyPackageViewDescriptorImpl.kt:37)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValue.invoke(LockBasedStorageManager.java:408)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedNotNullLazyValue.invoke(LockBasedStorageManager.java:527)
		at kotlin.reflect.jvm.internal.impl.storage.StorageKt.getValue(storage.kt:42)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.LazyPackageViewDescriptorImpl.getFragments(LazyPackageViewDescriptorImpl.kt:37)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.LazyPackageViewDescriptorImpl$memberScope$1.invoke(LazyPackageViewDescriptorImpl.kt:42)
		at kotlin.reflect.jvm.internal.impl.descriptors.impl.LazyPackageViewDescriptorImpl$memberScope$1.invoke(LazyPackageViewDescriptorImpl.kt:41)
		at kotlin.reflect.jvm.internal.impl.resolve.scopes.LazyScopeAdapter$lazyScope$1.invoke(LazyScopeAdapter.kt:28)
		at kotlin.reflect.jvm.internal.impl.resolve.scopes.LazyScopeAdapter$lazyScope$1.invoke(LazyScopeAdapter.kt:27)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValue.invoke(LockBasedStorageManager.java:408)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedNotNullLazyValue.invoke(LockBasedStorageManager.java:527)
		at kotlin.reflect.jvm.internal.impl.resolve.scopes.LazyScopeAdapter.getWorkerScope(LazyScopeAdapter.kt:34)
		at kotlin.reflect.jvm.internal.impl.resolve.scopes.AbstractScopeAdapter.getContributedClassifier(AbstractScopeAdapter.kt:44)
		at kotlin.reflect.jvm.internal.impl.descriptors.FindClassInModuleKt.findClassifierAcrossModuleDependencies(findClassInModule.kt:26)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer.computeClassifierDescriptor(TypeDeserializer.kt:240)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer.access$computeClassifierDescriptor(TypeDeserializer.kt:23)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer$classifierDescriptors$1.invoke(TypeDeserializer.kt:33)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer$classifierDescriptors$1.invoke(TypeDeserializer.kt:32)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$MapBasedMemoizedFunction.invoke(LockBasedStorageManager.java:578)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer.typeConstructor(TypeDeserializer.kt:132)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer.simpleType(TypeDeserializer.kt:76)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.TypeDeserializer.type(TypeDeserializer.kt:64)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedClassDescriptor$DeserializedClassTypeConstructor.computeSupertypes(DeserializedClassDescriptor.kt:193)
		at kotlin.reflect.jvm.internal.impl.types.AbstractTypeConstructor$supertypes$1.invoke(AbstractTypeConstructor.kt:82)
		at kotlin.reflect.jvm.internal.impl.types.AbstractTypeConstructor$supertypes$1.invoke(AbstractTypeConstructor.kt:82)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValue.invoke(LockBasedStorageManager.java:408)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValueWithPostCompute.invoke(LockBasedStorageManager.java:481)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedNotNullLazyValueWithPostCompute.invoke(LockBasedStorageManager.java:512)
		at kotlin.reflect.jvm.internal.impl.types.AbstractTypeConstructor.getSupertypes(AbstractTypeConstructor.kt:29)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedClassDescriptor$DeserializedClassMemberScope.getNonDeclaredVariableNames(DeserializedClassDescriptor.kt:309)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedMemberScope$OptimizedImplementation$variableNames$2.invoke(DeserializedMemberScope.kt:262)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedMemberScope$OptimizedImplementation$variableNames$2.invoke(DeserializedMemberScope.kt:261)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValue.invoke(LockBasedStorageManager.java:408)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedNotNullLazyValue.invoke(LockBasedStorageManager.java:527)
		at kotlin.reflect.jvm.internal.impl.storage.StorageKt.getValue(storage.kt:42)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedMemberScope$OptimizedImplementation.getVariableNames(DeserializedMemberScope.kt:261)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedMemberScope$OptimizedImplementation.addFunctionsAndPropertiesTo(DeserializedMemberScope.kt:349)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedMemberScope.computeDescriptors(DeserializedMemberScope.kt:115)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedClassDescriptor$DeserializedClassMemberScope$allDescriptors$1.invoke(DeserializedClassDescriptor.kt:230)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedClassDescriptor$DeserializedClassMemberScope$allDescriptors$1.invoke(DeserializedClassDescriptor.kt:229)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedLazyValue.invoke(LockBasedStorageManager.java:408)
		at kotlin.reflect.jvm.internal.impl.storage.LockBasedStorageManager$LockBasedNotNullLazyValue.invoke(LockBasedStorageManager.java:527)
		at kotlin.reflect.jvm.internal.impl.serialization.deserialization.descriptors.DeserializedClassDescriptor$DeserializedClassMemberScope.getContributedDescriptors(DeserializedClassDescriptor.kt:240)
		at kotlin.reflect.jvm.internal.impl.resolve.scopes.ResolutionScope$DefaultImpls.getContributedDescriptors$default(ResolutionScope.kt:50)
		at kotlin.reflect.jvm.internal.KDeclarationContainerImpl.getMembers(KDeclarationContainerImpl.kt:57)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$declaredNonStaticMembers$2.invoke(KClassImpl.kt:162)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$declaredNonStaticMembers$2.invoke(KClassImpl.kt:47)
		at kotlin.reflect.jvm.internal.ReflectProperties$LazySoftVal.invoke(ReflectProperties.java:92)
		at kotlin.reflect.jvm.internal.ReflectProperties$Val.getValue(ReflectProperties.java:31)
		at kotlin.reflect.jvm.internal.KClassImpl$Data.getDeclaredNonStaticMembers(KClassImpl.kt)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$allNonStaticMembers$2.invoke(KClassImpl.kt:171)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$allNonStaticMembers$2.invoke(KClassImpl.kt:47)
		at kotlin.reflect.jvm.internal.ReflectProperties$LazySoftVal.invoke(ReflectProperties.java:92)
		at kotlin.reflect.jvm.internal.ReflectProperties$Val.getValue(ReflectProperties.java:31)
		at kotlin.reflect.jvm.internal.KClassImpl$Data.getAllNonStaticMembers(KClassImpl.kt)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$allMembers$2.invoke(KClassImpl.kt:177)
		at kotlin.reflect.jvm.internal.KClassImpl$Data$allMembers$2.invoke(KClassImpl.kt:47)
		at kotlin.reflect.jvm.internal.ReflectProperties$LazySoftVal.invoke(ReflectProperties.java:92)
		at kotlin.reflect.jvm.internal.ReflectProperties$Val.getValue(ReflectProperties.java:31)
		at kotlin.reflect.jvm.internal.KClassImpl$Data.getAllMembers(KClassImpl.kt)
		at kotlin.reflect.jvm.internal.KClassImpl.getMembers(KClassImpl.kt:195)
		at kotlin.reflect.full.KClasses.getFunctions(KClasses.kt:90)
		at kotlin.reflect.jvm.ReflectJvmMapping.getKotlinFunction(ReflectJvmMapping.kt:136)
		at org.springframework.core.MethodParameter$KotlinDelegate.getReturnType(MethodParameter.java:932)
		at org.springframework.core.MethodParameter$KotlinDelegate.access$100(MethodParameter.java:866)
		at org.springframework.core.MethodParameter.computeParameterType(MethodParameter.java:538)
		at org.springframework.core.MethodParameter.getParameterType(MethodParameter.java:492)
		at org.springframework.web.reactive.result.method.InvocableHandlerMethod.lambda$invoke$0(InvocableHandlerMethod.java:168)
		at reactor.core.publisher.FluxFlatMap.trySubscribeScalarMap(FluxFlatMap.java:151)
		at reactor.core.publisher.MonoFlatMap.subscribeOrReturn(MonoFlatMap.java:53)
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:57)
		at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52)
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:154)
		at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56)
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64)
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:157)
		at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:73)
		at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82)
		at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.innerNext(FluxConcatMap.java:281)
		at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:860)
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onNext(FluxMapFuseable.java:127)
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180)
		at reactor.core.publisher.Operators$ScalarSubscription.request(Operators.java:2397)
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.request(MonoPeekTerminal.java:139)
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.request(FluxMapFuseable.java:169)
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.set(Operators.java:2193)
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.onSubscribe(Operators.java:2067)
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onSubscribe(FluxMapFuseable.java:96)
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onSubscribe(MonoPeekTerminal.java:152)
		at reactor.core.publisher.MonoJust.subscribe(MonoJust.java:54)
		at reactor.core.publisher.Mono.subscribe(Mono.java:4046)
		at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.drain(FluxConcatMap.java:448)
		at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onSubscribe(FluxConcatMap.java:218)
		at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:164)
		at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:86)
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64)
		at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52)
		at reactor.core.publisher.Mono.subscribe(Mono.java:4046)
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:173)
		at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56)
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64)
		at reactor.netty.http.server.HttpServer$HttpServerHandle.onStateChange(HttpServer.java:860)
		at reactor.netty.ReactorNetty$CompositeConnectionObserver.onStateChange(ReactorNetty.java:638)
		at reactor.netty.transport.ServerTransport$ChildObserver.onStateChange(ServerTransport.java:478)
		at reactor.netty.http.server.HttpServerOperations.onInboundNext(HttpServerOperations.java:525)
		at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:94)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
		at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:209)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
		at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436)
		at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324)
		at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296)
		at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
		at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
		at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919)
		at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166)
		at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719)
		at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655)
		at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581)
		at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
		at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989)
		at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
		at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
		at java.base/java.lang.Thread.run(Thread.java:834)

Faustas Butkus · Answer 3 · Sat Mar 20 2021 15:57:53 GMT+0800 (China Standard Time)

But providing integration into the install method:

BlockHound.install(CoroutinesBlockHoundIntegration())

fixes the problem. Thank you.