Fixes and improvements for -XX:+HeapDumpOnOutOfMemoryError.

Author: christianhaeubl

docs/reference-manual/native-image/guides/create-heap-dump-from-native-executable.md

@@ -7,15 +7,16 @@ permalink: /reference-manual/native-image/guides/create-heap-dump/
 
 # Create a Heap Dump from a Native Executable
 
-You can create a heap dump of a running executable to monitor its execution. Just like any other Java heap dump, it can be opened with the [VisualVM](../../../tools/visualvm.md) tool.
+You can create a heap dump of a running executable to monitor its execution.
+Just like any other Java heap dump, it can be opened with the [VisualVM](../../../tools/visualvm.md) tool.
 
 To enable heap dump support, native executables must be built with the `--enable-monitoring=heapdump` option. Heap dumps can then be created in different ways:
 
 1. Create heap dumps with VisualVM.
-2. Dump the initial heap of a native executable using the `-XX:+DumpHeapAndExit` command-line option.
-3. Create heap dumps sending a `SIGUSR1` signal at run time.
-4. Create heap dumps programmatically using the [`org.graalvm.nativeimage.VMRuntime#dumpHeap`](https://github.com/oracle/graal/blob/master/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/VMInspectionOptions.java) API.
-5. If `-XX:+HeapDumpOnOutOfMemoryError` is passed in at runtime and an `OutOfMemoryError` is encountered, a heap dump will be produced.
+2. The command-line option `-XX:+HeapDumpOnOutOfMemoryError` can be used to create a heap dump when the native executable runs out of Java heap memory.
+3. Dump the initial heap of a native executable using the `-XX:+DumpHeapAndExit` command-line option.
+4. Create heap dumps sending a `SIGUSR1` signal at run time.
+5. Create heap dumps programmatically using the [`org.graalvm.nativeimage.VMRuntime#dumpHeap`](https://github.com/oracle/graal/blob/master/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/VMInspectionOptions.java) API.
 
 All approaches are described below.
 
@@ -31,6 +32,18 @@ For this, you need to add `jvmstat` to the `--enable-monitoring` option (for exa
 This will allow VisualVM to pick up and list running Native Image processes.
 You can then request heap dumps in the same way you can request them when your application runs on the JVM (for example, right-click on the process, then select "Heap Dump").
 
+## Create a Heap Dump on `OutOfMemoryError`
+
+Start the application with the option `-XX:+HeapDumpOnOutOfMemoryError` to get a heap dump when the native executable throws an `OutOfMemoryError` because it ran out of Java heap memory.
+The heap dump is created in a file named `svm-heapdump-<PID>-OOME.hprof`.
+For example:
+
+```shell
+./mem-leak-example -XX:+HeapDumpOnOutOfMemoryError
+Dumping heap to svm-heapdump-67799-OOME.hprof ...
+Exception in thread "main" java.lang.OutOfMemoryError: Garbage-collected heap size exceeded.
+```
+
 ## Dump the Initial Heap of a Native Executable
 
 Use the `-XX:+DumpHeapAndExit` command-line option to dump the initial heap of a native executable.
@@ -96,6 +109,7 @@ For other installation options, visit the [Downloads section](https://www.graalv
             for (int i = 0; i < 1000; i++) {
                 CROWD.add(new Person());
             }
+
             long pid = ProcessProperties.getProcessID();
             StringBuffer sb1 = new StringBuffer(100);
             sb1.append(DATE_FORMATTER.format(new Date()));
@@ -106,6 +120,7 @@ For other installation options, visit the [Downloads section](https://www.graalv
             sb1.append("to dump the heap into the working directory.\n");
             sb1.append("Starting thread!");
             System.out.println(sb1);
+
             SVMHeapDump t = new SVMHeapDump();
             t.start();
             while (t.isAlive()) {
@@ -121,17 +136,17 @@ For other installation options, visit the [Downloads section](https://www.graalv
     }
 
     class Person {
-            private static Random R = new Random();
-            private String name;
-            private int age;
+        private static Random R = new Random();
+        private String name;
+        private int age;
 
-            public Person() {
-                byte[] array = new byte[7];
-                R.nextBytes(array);
-                name = new String(array, Charset.forName("UTF-8"));
-                age = R.nextInt(100);
-            }
+        public Person() {
+            byte[] array = new byte[7];
+            R.nextBytes(array);
+            name = new String(array, Charset.forName("UTF-8"));
+            age = R.nextInt(100);
         }
+    }
     ```
 
 3. Build a native executable:
@@ -276,18 +291,6 @@ The condition to create a heap dump is provided as an option on the command line
 
     ![Native Image Heap Dump View in VisualVM](img/heap-dump-api.png)
 
-## Create a Heap Dump on `OutOfMemoryError`
-
-Start the application with `-XX:+HeapDumpOnOutOfMemoryError` option to get a heap dump when an `OutOfMemoryError` occurs.
-The generated heap dump file name will have the `svm-heapdump-<PID>.hprof` naming format.
-For example:
-
-```shell
-./example -XX:+HeapDumpOnOutOfMemoryError
-Dumping heap to svm-heapdump-67799.hprof ...
-Exception in thread "main" java.lang.OutOfMemoryError: Garbage-collected heap size exceeded.
-```
-
 ### Related Documentation
 
 * [Debugging and Diagnostics](../DebuggingAndDiagnostics.md)

sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/VMRuntime.java

@@ -92,20 +92,6 @@ public static void dumpHeap(String outputFile, boolean live) throws IOException
         ImageSingletons.lookup(HeapDumpSupport.class).dumpHeap(outputFile, live);
     }
 
-    /**
-     * Dumps the heap to a predetermined file in case of an @{@link OutOfMemoryError}, in the same format as the hprof heap dump.
-     *
-     * @throws UnsupportedOperationException if this operation is not supported.
-     *
-     * @since 23.1
-     */
-    public static void dumpHeapOnOutOfMemoryError() {
-        if (!ImageSingletons.contains(HeapDumpSupport.class)) {
-            throw new UnsupportedOperationException();
-        }
-        ImageSingletons.lookup(HeapDumpSupport.class).dumpHeapOnOutOfMemoryError();
-    }
-
     private VMRuntime() {
     }
 }

sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/impl/HeapDumpSupport.java

@@ -44,7 +44,4 @@ public interface HeapDumpSupport {
 
     void dumpHeap(String outputFile, boolean live) throws java.io.IOException;
 
-    void dumpHeapOnOutOfMemoryError();
-
-    void initHeapDumpOnOutOfMemoryErrorPath();
 }

substratevm/CHANGELOG.md

@@ -10,6 +10,7 @@ This changelog summarizes major changes to GraalVM Native Image.
 * (GR-39406) All classes can now be used at image build time, even when they are not explicitly configured as `--initialize-at-build-time`. Note, however, that still only classes configured as `--initialize-at-build-time` are allowed in the image heap.
 * (GR-46392) Add `--parallelism` option to control how many threads are used by the build process.
 * (GR-46392) Add build resources section to the build output that shows the memory and thread limits of the build process.
+* (GR-38994) Together with Red Hat, we added support for `-XX:+HeapDumpOnOutOfMemoryError`.
 
 ## Version 23.0.0
 * (GR-40187) Report invalid use of SVM specific classes on image class- or module-path as error. As a temporary workaround, `-H:+AllowDeprecatedBuilderClassesOnImageClasspath` allows turning the error into a warning.

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/GCImpl.java

@@ -29,14 +29,12 @@
 
 import java.lang.ref.Reference;
 
-import com.oracle.svm.core.jdk.UninterruptibleUtils.AtomicBoolean;
 import org.graalvm.compiler.api.replacements.Fold;
 import org.graalvm.nativeimage.CurrentIsolate;
 import org.graalvm.nativeimage.IsolateThread;
 import org.graalvm.nativeimage.Platform;
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.nativeimage.StackValue;
-import org.graalvm.nativeimage.VMRuntime;
 import org.graalvm.nativeimage.c.function.CodePointer;
 import org.graalvm.nativeimage.c.struct.RawField;
 import org.graalvm.nativeimage.c.struct.RawStructure;
@@ -118,8 +116,6 @@ public final class GCImpl implements GC {
     private UnsignedWord collectionEpoch = WordFactory.zero();
     private long lastWholeHeapExaminedTimeMillis = -1;
 
-    private final AtomicBoolean outOfMemoryReported = new AtomicBoolean(false);
-
     @Platforms(Platform.HOSTED_ONLY.class)
     GCImpl() {
         this.policy = CollectionPolicy.getInitialPolicy();
@@ -154,17 +150,10 @@ public void maybeCollectOnAllocation() {
             outOfMemory = collectWithoutAllocating(GenScavengeGCCause.OnAllocation, false);
         }
         if (outOfMemory) {
-            reportJavaOutOfMemory();
             throw OutOfMemoryUtil.heapSizeExceeded();
         }
     }
 
-    private void reportJavaOutOfMemory() {
-        if (SubstrateOptions.isHeapDumpOnOutOfMemoryError() && outOfMemoryReported.compareAndSet(false, true)) {
-            VMRuntime.dumpHeapOnOutOfMemoryError();
-        }
-    }
-
     @Override
     public void maybeCauseUserRequestedCollection(GCCause cause, boolean fullGC) {
         if (policy.shouldCollectOnRequest(cause, fullGC)) {
@@ -176,7 +165,6 @@ private void collect(GCCause cause, boolean forceFullGC) {
         if (!hasNeverCollectPolicy()) {
             boolean outOfMemory = collectWithoutAllocating(cause, forceFullGC);
             if (outOfMemory) {
-                reportJavaOutOfMemory();
                 throw OutOfMemoryUtil.heapSizeExceeded();
             }
         }

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/PosixRawFileOperationSupport.java

@@ -32,6 +32,7 @@
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.nativeimage.c.type.CCharPointer;
 import org.graalvm.nativeimage.c.type.CTypeConversion;
+import org.graalvm.nativeimage.impl.UnmanagedMemorySupport;
 import org.graalvm.word.Pointer;
 import org.graalvm.word.SignedWord;
 import org.graalvm.word.UnsignedWord;
@@ -54,6 +55,21 @@ public PosixRawFileOperationSupport(boolean useNativeByteOrder) {
         super(useNativeByteOrder);
     }
 
+    @Override
+    public CCharPointer allocateCPath(String path) {
+        byte[] data = path.getBytes();
+        CCharPointer filename = ImageSingletons.lookup(UnmanagedMemorySupport.class).malloc(WordFactory.unsigned(data.length + 1));
+        if (filename.isNull()) {
+            return WordFactory.nullPointer();
+        }
+
+        for (int i = 0; i < data.length; i++) {
+            filename.write(i, data[i]);
+        }
+        filename.write(data.length, (byte) 0);
+        return filename;
+    }
+
     @Override
     public RawFileDescriptor create(File file, FileCreationMode creationMode, FileAccessMode accessMode) {
         String path = file.getPath();
@@ -62,16 +78,12 @@ public RawFileDescriptor create(File file, FileCreationMode creationMode, FileAc
     }
 
     @Override
+    @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
     public RawFileDescriptor create(CCharPointer cPath, FileCreationMode creationMode, FileAccessMode accessMode) {
         int flags = parseMode(creationMode) | parseMode(accessMode);
         return open0(cPath, flags);
     }
 
-    private static RawFileDescriptor open0(CCharPointer cPath, int flags) {
-        int permissions = PosixStat.S_IRUSR() | PosixStat.S_IWUSR();
-        return WordFactory.signed(Fcntl.NoTransitions.open(cPath, flags, permissions));
-    }
-
     @Override
     public RawFileDescriptor open(File file, FileAccessMode mode) {
         String path = file.getPath();
@@ -80,18 +92,24 @@ public RawFileDescriptor open(File file, FileAccessMode mode) {
     }
 
     @Override
+    @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
     public RawFileDescriptor open(CCharPointer cPath, FileAccessMode mode) {
         int flags = parseMode(mode);
         return open0(cPath, flags);
     }
 
     private static RawFileDescriptor open0(String path, int flags) {
-        int permissions = PosixStat.S_IRUSR() | PosixStat.S_IWUSR();
         try (CTypeConversion.CCharPointerHolder cPath = CTypeConversion.toCString(path)) {
-            return WordFactory.signed(Fcntl.NoTransitions.open(cPath.get(), flags, permissions));
+            return open0(cPath.get(), flags);
         }
     }
 
+    @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
+    private static RawFileDescriptor open0(CCharPointer cPath, int flags) {
+        int permissions = PosixStat.S_IRUSR() | PosixStat.S_IWUSR();
+        return WordFactory.signed(Fcntl.NoTransitions.open(cPath, flags, permissions));
+    }
+
     @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
     @Override
     public boolean isValid(RawFileDescriptor fd) {
@@ -172,6 +190,7 @@ private static int getPosixFileDescriptor(RawFileDescriptor fd) {
         return result;
     }
 
+    @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
     private static int parseMode(FileCreationMode mode) {
         switch (mode) {
             case CREATE:
@@ -183,6 +202,7 @@ private static int parseMode(FileCreationMode mode) {
         }
     }
 
+    @Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
     private static int parseMode(FileAccessMode mode) {
         switch (mode) {
             case READ:

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/DumpHeapOnSignalFeature.java

@@ -25,64 +25,57 @@
 package com.oracle.svm.core;
 
 import java.io.IOException;
-import java.text.DateFormat;
-import java.text.SimpleDateFormat;
-import java.util.Date;
-import java.util.TimeZone;
-
-import org.graalvm.nativeimage.ImageSingletons;
-import org.graalvm.nativeimage.ProcessProperties;
-import org.graalvm.nativeimage.VMRuntime;
 
 import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 import com.oracle.svm.core.feature.InternalFeature;
+import com.oracle.svm.core.heap.dump.HeapDumping;
 import com.oracle.svm.core.jdk.RuntimeSupport;
 import com.oracle.svm.core.log.Log;
 
 import jdk.internal.misc.Signal;
-import org.graalvm.nativeimage.impl.HeapDumpSupport;
 
 @AutomaticallyRegisteredFeature
 public class DumpHeapOnSignalFeature implements InternalFeature {
-
-    @Override
-    public boolean isInConfiguration(IsInConfigurationAccess access) {
-        return VMInspectionOptions.hasHeapDumpSupport();
-    }
-
     @Override
     public void beforeAnalysis(BeforeAnalysisAccess access) {
-        RuntimeSupport.getRuntimeSupport().addStartupHook(new DumpHeapStartupHook());
+        if (HeapDumping.isSupported()) {
+            RuntimeSupport.getRuntimeSupport().addInitializationHook(new DumpHeapStartupHook());
+            RuntimeSupport.getRuntimeSupport().addTearDownHook(new DumpHeapTeardownHook());
+        }
     }
 }
 
 final class DumpHeapStartupHook implements RuntimeSupport.Hook {
     @Override
     public void execute(boolean isFirstIsolate) {
-        if (isFirstIsolate && SubstrateOptions.EnableSignalHandling.getValue()) {
-            DumpHeapReport.install();
-            if (SubstrateOptions.isHeapDumpOnOutOfMemoryError()) {
-                ImageSingletons.lookup(HeapDumpSupport.class).initHeapDumpOnOutOfMemoryErrorPath();
+        if (HeapDumping.isSupported()) {
+            if (VMInspectionOptions.useHeapDumpSignalHandler() && isFirstIsolate && SubstrateOptions.EnableSignalHandling.getValue()) {
+                DumpHeapReport.install();
             }
+
+            HeapDumping.singleton().initialize();
         }
     }
 }
 
-class DumpHeapReport implements Signal.Handler {
-    private static final TimeZone UTC_TIMEZONE = TimeZone.getTimeZone("UTC");
+final class DumpHeapTeardownHook implements RuntimeSupport.Hook {
+    @Override
+    public void execute(boolean isFirstIsolate) {
+        if (HeapDumping.isSupported()) {
+            HeapDumping.singleton().teardown();
+        }
+    }
+}
 
+class DumpHeapReport implements Signal.Handler {
     static void install() {
         Signal.handle(new Signal("USR1"), new DumpHeapReport());
     }
 
     @Override
     public void handle(Signal arg0) {
-        DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd'T'HHmmss'Z'");
-        dateFormat.setTimeZone(UTC_TIMEZONE);
-        String defaultHeapDumpFileName = "svm-heapdump-" + ProcessProperties.getProcessID() + "-" + dateFormat.format(new Date()) + ".hprof";
-        String heapDumpPath = SubstrateOptions.getHeapDumpPath(defaultHeapDumpFileName);
         try {
-            VMRuntime.dumpHeap(heapDumpPath, true);
+            HeapDumping.singleton().dumpHeap(true);
         } catch (IOException e) {
             Log.log().string("IOException during dumpHeap: ").string(e.getMessage()).newline();
         }