https://kotlinlang.org logo
Join Slack
Powered by
I'm using ktor client with the CIO engine for my k...
# ktor
j
I'm using ktor client with the CIO engine for my kt-search client (a rest client for opensearch and elasticsearch). We recently switched to this with our main application (Spring Boot) and now running our multi threaded tests (we run with ten or so junit threads), I get a few weird exceptions that randomly fail small portion of the tests (see stacktrace below) After a bit of digging, I narrowed the problem down to the CIO engine and I suspect it's not completely threadsafe somehow. Switching to the Java engine makes the problem go away completely. I haven't tried any of the other engines. The previous version of the client would have used Elastic's RestHighLevel client, which in turn uses Apache http client if I recall correctly. So the main change here is that we are now using a different Rest client. Looking at the documentation, I wonder if there is any guidance on pros/cons of each engine. There seem to be a lot of them at least. For reference, this is the stack trace. It looks to me like different threads are ending up trying to open the same port somehow or messing with the same connection.
Copy code
java.net.BindException: Can't assign requested address
	at java.base/sun.nio.ch.Net.connect0(Native Method)
	at java.base/sun.nio.ch.Net.connect(Net.java:579)
	at java.base/sun.nio.ch.Net.connect(Net.java:586)
	at java.base/sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:853)
	at io.ktor.network.sockets.SocketImpl.connect$ktor_network(SocketImpl.kt:44)
	at io.ktor.network.sockets.ConnectUtilsJvmKt.connect(ConnectUtilsJvm.kt:21)
	at io.ktor.network.sockets.TcpSocketBuilder.connect(TcpSocketBuilder.kt:37)
	at io.ktor.client.engine.cio.ConnectionFactory.connect(ConnectionFactory.kt:29)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invokeSuspend(Endpoint.kt:156)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at kotlinx.coroutines.intrinsics.UndispatchedKt.startUndispatchedOrReturnIgnoreTimeout(Undispatched.kt:100)
	at kotlinx.coroutines.TimeoutKt.setupTimeout(Timeout.kt:146)
	at kotlinx.coroutines.TimeoutKt.withTimeoutOrNull(Timeout.kt:103)
	at io.ktor.client.engine.cio.Endpoint.connect(Endpoint.kt:164)
	at io.ktor.client.engine.cio.Endpoint.makeDedicatedRequest(Endpoint.kt:98)
	at io.ktor.client.engine.cio.Endpoint.execute(Endpoint.kt:62)
	at io.ktor.client.engine.cio.CIOEngine.execute(CIOEngine.kt:84)
	at io.ktor.client.engine.HttpClientEngine$executeWithinCallContext$2.invokeSuspend(HttpClientEngine.kt:99)
	at ???(Coroutine boundary.?(?)
	at io.ktor.client.engine.HttpClientEngine$DefaultImpls.executeWithinCallContext(HttpClientEngine.kt:100)
	at io.ktor.client.engine.HttpClientEngine$install$1.invokeSuspend(HttpClientEngine.kt:70)
	at io.ktor.client.plugins.HttpSend$DefaultSender.execute(HttpSend.kt:138)
	at io.ktor.client.plugins.HttpRedirect$Plugin$install$1.invokeSuspend(HttpRedirect.kt:61)
	at io.ktor.client.plugins.HttpCallValidator$Companion$install$3.invokeSuspend(HttpCallValidator.kt:147)
	at io.ktor.client.plugins.HttpSend$Plugin$install$1.invokeSuspend(HttpSend.kt:104)
	at io.ktor.client.plugins.DefaultTransformKt$defaultTransformers$1.invokeSuspend(DefaultTransform.kt:53)
	at io.ktor.client.plugins.HttpCallValidator$Companion$install$1.invokeSuspend(HttpCallValidator.kt:126)
	at io.ktor.client.plugins.HttpRequestLifecycle$Plugin$install$1.invokeSuspend(HttpRequestLifecycle.kt:35)
	at io.ktor.client.HttpClient.execute$ktor_client_core(HttpClient.kt:191)
	at io.ktor.client.statement.HttpStatement.executeUnsafe(HttpStatement.kt:108)
	at io.ktor.client.statement.HttpStatement.execute(HttpStatement.kt:47)
	at com.tryformation.api.graphql.FormationClient.executeRaw(FormationClient.kt:1037)
	at com.tryformation.api.graphql.FormationClient.execute(FormationClient.kt:919)
	at com.tryformation.graphqlapi.TestTeamAndClientCreator.createTeam$suspendImpl(APITest.kt:211)
	at com.tryformation.graphqlapi.analytics.ArmyTestFixture.create(ArmyTestFixture.kt:272)
	at com.tryformation.graphqlapi.analytics.ArmyTestFixture$armyWorkspace$2$1.invokeSuspend(ArmyTestFixture.kt:269)
	at com.tryformation.graphqlapi.TestbeansKt$runTest$1.invokeSuspend(testbeans.kt:257)
Caused by: java.net.BindException: Can't assign requested address
	at java.base/sun.nio.ch.Net.connect0(Native Method)
	at java.base/sun.nio.ch.Net.connect(Net.java:579)
	at java.base/sun.nio.ch.Net.connect(Net.java:586)
	at java.base/sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:853)
	at io.ktor.network.sockets.SocketImpl.connect$ktor_network(SocketImpl.kt:44)
	at io.ktor.network.sockets.ConnectUtilsJvmKt.connect(ConnectUtilsJvm.kt:21)
	at io.ktor.network.sockets.TcpSocketBuilder.connect(TcpSocketBuilder.kt:37)
	at io.ktor.client.engine.cio.ConnectionFactory.connect(ConnectionFactory.kt:29)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invokeSuspend(Endpoint.kt:156)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at kotlinx.coroutines.intrinsics.UndispatchedKt.startUndispatchedOrReturnIgnoreTimeout(Undispatched.kt:100)
	at kotlinx.coroutines.TimeoutKt.setupTimeout(Timeout.kt:146)
	at kotlinx.coroutines.TimeoutKt.withTimeoutOrNull(Timeout.kt:103)
	at io.ktor.client.engine.cio.Endpoint.connect(Endpoint.kt:164)
	at io.ktor.client.engine.cio.Endpoint.makeDedicatedRequest(Endpoint.kt:98)
	at io.ktor.client.engine.cio.Endpoint.execute(Endpoint.kt:62)
	at io.ktor.client.engine.cio.CIOEngine.execute(CIOEngine.kt:84)
	at io.ktor.client.engine.HttpClientEngine$executeWithinCallContext$2.invokeSuspend(HttpClientEngine.kt:99)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
	at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
	at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)
🧵 1
a
Can you share a code snippet to reproduce the 
BindException
?
j
It's not a simple test. It's hundreds of integration tests running with 10+ threads as fast as they can doing thousands of requests against Elasticsearch. So, not simple to reproduce.
It's never the same tests that fail and they all pass when you run them individually.
a
I’ve reproduced it with the following code:
Copy code
val client = HttpClient(CIO)

coroutineScope {
    (1..40000).map {
        async {
            client.get("<http://localhost:8888>")
        }
    }.awaitAll()
}
Here is the issue.
j
Thanks for this!
328 Views
Open in Slack
PreviousNext
Powered by