8369736: Add management interface for AOT cache creation

Reviewed-by: mr, iklam, kevinw

Author: Mat Carter

src/hotspot/share/cds/aotMetaspace.cpp

@@ -96,6 +96,7 @@
 #include "runtime/vmOperations.hpp"
 #include "runtime/vmThread.hpp"
 #include "sanitizers/leak.hpp"
+#include "services/management.hpp"
 #include "utilities/align.hpp"
 #include "utilities/bitMap.inline.hpp"
 #include "utilities/defaultStream.hpp"

src/hotspot/share/include/jvm.h

@@ -87,6 +87,9 @@ JVM_InternString(JNIEnv *env, jstring str);
 /*
  * java.lang.System
  */
+JNIEXPORT jboolean JNICALL
+JVM_AOTEndRecording(JNIEnv *env);
+
 JNIEXPORT jlong JNICALL
 JVM_CurrentTimeMillis(JNIEnv *env, jclass ignored);
 

src/hotspot/share/prims/jvm.cpp

@@ -229,6 +229,19 @@ extern void trace_class_resolution(Klass* to_class) {
 
 // java.lang.System //////////////////////////////////////////////////////////////////////
 
+JVM_ENTRY(jboolean, JVM_AOTEndRecording(JNIEnv *env))
+#if INCLUDE_CDS
+  if (CDSConfig::is_dumping_preimage_static_archive()) {
+    if (!AOTMetaspace::preimage_static_archive_dumped()) {
+      AOTMetaspace::dump_static_archive(THREAD);
+      return JNI_TRUE;
+    }
+  }
+  return JNI_FALSE;
+#else
+  return JNI_FALSE;
+#endif // INCLUDE_CDS
+JVM_END
 
 JVM_LEAF(jlong, JVM_CurrentTimeMillis(JNIEnv *env, jclass ignored))
   return os::javaTimeMillis();

src/java.management/share/classes/sun/management/VMManagement.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -48,6 +48,9 @@ public interface VMManagement {
     public boolean isGcNotificationSupported();
     public boolean isRemoteDiagnosticCommandsSupported();
 
+    // AOT Subsystem
+    public boolean endAOTRecording();
+
     // Class Loading Subsystem
     public long    getTotalClassCount();
     public int     getLoadedClassCount();

src/java.management/share/classes/sun/management/VMManagementImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -117,6 +117,9 @@ public boolean isRemoteDiagnosticCommandsSupported() {
     public native boolean isThreadCpuTimeEnabled();
     public native boolean isThreadAllocatedMemoryEnabled();
 
+    // AOT Subsystem
+    public native boolean endAOTRecording();
+
     // Class Loading Subsystem
     public int    getLoadedClassCount() {
         long count = getTotalClassCount() - getUnloadedClassCount();

src/java.management/share/native/libmanagement/VMManagementImpl.c

@@ -101,6 +101,13 @@ Java_sun_management_VMManagementImpl_getVmArguments0
     return JVM_GetVmArguments(env);
 }
 
+JNIEXPORT jboolean JNICALL
+Java_sun_management_VMManagementImpl_endAOTRecording
+  (JNIEnv *env, jobject dummy)
+{
+    return JVM_AOTEndRecording(env);
+}
+
 JNIEXPORT jlong JNICALL
 Java_sun_management_VMManagementImpl_getTotalClassCount
   (JNIEnv *env, jobject dummy)

src/jdk.management/share/classes/com/sun/management/internal/HotSpotAOTCacheImpl.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2025, Microsoft, Inc. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.sun.management.internal;
+
+import javax.management.ObjectName;
+import jdk.management.HotSpotAOTCacheMXBean;
+import sun.management.Util;
+import sun.management.VMManagement;
+
+/**
+ * Implementation class for the AOT Cache subsystem.
+ *
+ * ManagementFactory.getRuntimeMXBean() returns an instance
+ * of this class.
+ */
+public class HotSpotAOTCacheImpl implements HotSpotAOTCacheMXBean {
+
+    private final VMManagement jvm;
+    /**
+     * Constructor of HotSpotAOTCacheImpl class.
+     */
+    HotSpotAOTCacheImpl(VMManagement vm) {
+        this.jvm = vm;
+    }
+
+    public boolean endRecording() {
+        return jvm.endAOTRecording();
+    }
+
+    public ObjectName getObjectName() {
+        return Util.newObjectName("jdk.management:type=HotSpotAOTCache");
+    }
+}

src/jdk.management/share/classes/com/sun/management/internal/PlatformMBeanProviderImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -39,6 +39,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import javax.management.DynamicMBean;
+import jdk.management.HotSpotAOTCacheMXBean;
 import jdk.management.VirtualThreadSchedulerMXBean;
 import sun.management.ManagementFactoryHelper;
 import sun.management.spi.PlatformMBeanProvider;
@@ -159,6 +160,41 @@ public synchronized Map<String, java.lang.management.ThreadMXBean> nameToMBeanMa
             }
         });
 
+        /**
+        * HotSpotAOTCacheMXBean.
+        */
+        initMBeanList.add(new PlatformComponent<HotSpotAOTCacheMXBean>() {
+            private final Set<Class<? extends HotSpotAOTCacheMXBean>> mbeanInterfaces =
+                    Set.of(HotSpotAOTCacheMXBean.class);
+            private final Set<String> mbeanInterfaceNames =
+                    Set.of(HotSpotAOTCacheMXBean.class.getName());
+            private HotSpotAOTCacheMXBean impl;
+
+            @Override
+            public Set<Class<? extends HotSpotAOTCacheMXBean>> mbeanInterfaces() {
+                return mbeanInterfaces;
+            }
+
+            @Override
+            public Set<String> mbeanInterfaceNames() {
+                return mbeanInterfaceNames;
+            }
+
+            @Override
+            public String getObjectNamePattern() {
+                return "jdk.management:type=HotSpotAOTCache";
+            }
+
+            @Override
+            public Map<String, HotSpotAOTCacheMXBean> nameToMBeanMap() {
+                HotSpotAOTCacheMXBean impl = this.impl;
+                if (impl == null) {
+                    this.impl = impl = new HotSpotAOTCacheImpl(ManagementFactoryHelper.getVMManagement());
+                }
+                return Map.of("jdk.management:type=HotSpotAOTCache", impl);
+            }
+        });
+
         /**
          * VirtualThreadSchedulerMXBean.
          */

src/jdk.management/share/classes/jdk/management/HotSpotAOTCacheMXBean.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2025, Microsoft, Inc. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package jdk.management;
+
+import java.lang.management.ManagementFactory;
+import java.lang.management.PlatformManagedObject;
+import javax.management.MBeanServer;
+import javax.management.ObjectName;
+
+/**
+ * Management interface for the JDK's Ahead of Time (AOT) Cache.
+ *
+ * <p> The management interface is registered with the platform {@link MBeanServer
+ * MBeanServer}. The {@link ObjectName ObjectName} that uniquely identifies the management
+ * interface within the {@code MBeanServer} is {@code jdk.management:type=HotSpotAOTCache}.
+ *
+ * <p> Direct access to the MXBean interface can be obtained with
+ * {@link ManagementFactory#getPlatformMXBean(Class)}.
+ *
+ * @since 26
+ */
+public interface HotSpotAOTCacheMXBean extends PlatformManagedObject {
+    /**
+     * If an AOT recording is in progress, ends the recording. This method returns
+     * after the AOT artifacts have been completely written.
+     *
+     * <p>The JVM will start recording AOT artifacts upon start-up if appropriate JVM options are
+     * given in the command-line. The recording will stop when the JVM exits, or when
+     * the {@code endRecording} method is called. Examples:
+     *
+     * <p> ${@code java -XX:AOTCacheOutput=app.aot ....}
+     *
+     * <blockquote>
+     *    The JVM records optimization information for the current application in the AOT cache file
+     *    {@code app.aot}. In a future run of the application, the option {@code -XX:AOTCache=app.aot} will
+     *    cause the JVM to use the cache to improve the application's startup and warmup performance.
+     * </blockquote>
+     *
+     * <p>  ${@code java -XX:AOTMode=record -XX:AOTConfiguration=app.aotconfig ....}
+     *
+     * <blockquote>
+     *    The JVM records optimization information for the current application in the AOT configuration
+     *    file {@code app.aotconfig}. Subsequently, an AOT cache file can be created with the command:
+     *
+     *    <p>${@code java -XX:AOTMode=create -XX:AOTConfiguration=app.aotconfig  -XX:AOTCache=app.aot ...}
+     *  </blockquote>
+     *
+     * <p>For more information about creating and using the AOT artifacts, and detailed
+     * specification of the corresponding JVM command-line options, please refer
+     * to <a href="https://openjdk.org/jeps/483">JEP 483</a> and <a href="https://openjdk.org/jeps/514">JEP 514</a>.
+     *
+     * <p>Currently there are no APIs to start an AOT recording. AOT recordings must be
+     * started using JVM command-line options such as {@code -XX:AOTCacheOutput}.
+     * There are also no APIs to query whether an AOT recording is in progress, or what AOT
+     * artifacts are being recorded.
+     *
+     * <p> This method enables an application to end its own AOT recording
+     * programatically, but that is not necessarily the best approach. Doing so
+     * requires changing the application’s code, which might not be
+     * feasible. Even when it is feasible, injecting training-specific logic
+     * into the application reduces the similarity between training runs and
+     * production runs, potentially making the AOT cache less effective. It may
+     * be better to arrange for an external agent to end the training run,
+     * thereby creating an AOT cache without interfering with the application’s
+     * code.
+     *
+     * @return {@code true} if a recording was in progress and has been ended
+     * successfully; {@code false} otherwise.
+     */
+    public boolean endRecording();
+}