OutOfMemory Error after updating corda version to 4.1

Question

I had a corda 3.3 test installation and recently updated it to version 4.1 and after that when I run my nodes with deployNodes script and runnodes - I always receive the following exception in node's console as soon as it starts. What can this mean? I don't have a clue what this can be caused by. I tried to build and run the nodes without cordapps and they work, so somehow my cordapps cause this error happen. What other information should I provide to help you figure out this issue?

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOf(Arrays.java:3236)
at java.io.ByteArrayOutputStream.toByteArray(ByteArrayOutputStream.java:191)
at kotlin.io.ByteStreamsKt.readBytes(IOStreams.kt:123)
at kotlin.io.ByteStreamsKt.readBytes$default(IOStreams.kt:120)
at net.corda.core.internal.InternalUtils.readFully(InternalUtils.kt:123)
at net.corda.node.internal.cordapp.JarScanningCordappLoader.getJarHash(JarScanningCordappLoader.kt:228)
at net.corda.node.internal.cordapp.JarScanningCordappLoader.toCordapp(JarScanningCordappLoader.kt:153)
at net.corda.node.internal.cordapp.JarScanningCordappLoader.loadCordapps(JarScanningCordappLoader.kt:106)
at net.corda.node.internal.cordapp.JarScanningCordappLoader.access$loadCordapps(JarScanningCordappLoader.kt:44)
at net.corda.node.internal.cordapp.JarScanningCordappLoader$cordapps$2.invoke(JarScanningCordappLoader.kt:56)
at net.corda.node.internal.cordapp.JarScanningCordappLoader$cordapps$2.invoke(JarScanningCordappLoader.kt:44)
at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
at net.corda.node.internal.cordapp.JarScanningCordappLoader.getCordapps(JarScanningCordappLoader.kt)
at net.corda.node.internal.cordapp.CordappLoaderTemplate$cordappSchemas$2.invoke(JarScanningCordappLoader.kt:422)
at net.corda.node.internal.cordapp.CordappLoaderTemplate$cordappSchemas$2.invoke(JarScanningCordappLoader.kt:389)
at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
at net.corda.node.internal.cordapp.CordappLoaderTemplate.getCordappSchemas(JarScanningCordappLoader.kt)
at net.corda.node.internal.AbstractNode.<init>(AbstractNode.kt:153)
at net.corda.node.internal.AbstractNode.<init>(AbstractNode.kt:126)
at net.corda.node.internal.Node.<init>(Node.kt:98)
at net.corda.node.internal.Node.<init>(Node.kt:97)
at net.corda.node.internal.NodeStartup.createNode(NodeStartup.kt:194)
at net.corda.node.internal.NodeStartup$initialiseAndRun$5.invoke(NodeStartup.kt:186)
at net.corda.node.internal.NodeStartup$initialiseAndRun$5.invoke(NodeStartup.kt:137)
at net.corda.node.internal.NodeStartupLogging$DefaultImpls.attempt(NodeStartup.kt:509)
at net.corda.node.internal.NodeStartup.attempt(NodeStartup.kt:137)
at net.corda.node.internal.NodeStartup.initialiseAndRun(NodeStartup.kt:185)
at net.corda.node.internal.NodeStartupCli.runProgram(NodeStartup.kt:128)
at net.corda.cliutils.CordaCliWrapper.call(CordaCliWrapper.kt:190)
at net.corda.node.internal.NodeStartupCli.call(NodeStartup.kt:83)
at net.corda.node.internal.NodeStartupCli.call(NodeStartup.kt:64)
at picocli.CommandLine.execute(CommandLine.java:1056)

Answer 1

Corda's usage of memory has been slowly creeping upwards. It is possible that your machine does not have enough memory to run 3/4+ nodes at the same time after upgrading to 4.

I recommend trying to run a single node with CorDapps installed and see what happens. If it is still happening then, then something else could be going wrong.

Looking at the stacktrace, it is also possible that your CorDapp itself is really, really, really big and it has gone out of memory reading and loading the CorDapp.