HDDS-13065. Refactor SnapshotCache to return AutoCloseSupplier instead of ReferenceCounted

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/freon/TestOMSnapshotDAG.java

@@ -57,12 +57,12 @@
 import org.apache.hadoop.ozone.om.helpers.OmBucketInfo;
 import org.apache.hadoop.ozone.om.helpers.OmVolumeArgs;
 import org.apache.hadoop.ozone.om.helpers.SnapshotInfo;
-import org.apache.hadoop.ozone.om.snapshot.ReferenceCounted;
 import org.apache.ozone.rocksdiff.DifferSnapshotInfo;
 import org.apache.ozone.rocksdiff.RocksDBCheckpointDiffer;
 import org.apache.ozone.test.GenericTestUtils;
 import org.apache.ratis.server.RaftServer;
 import org.apache.ratis.server.raftlog.RaftLog;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
@@ -212,9 +212,9 @@ public void testDAGReconstruction()
     OMMetadataManager omMetadataManager = ozoneManager.getMetadataManager();
     RDBStore rdbStore = (RDBStore) omMetadataManager.getStore();
     RocksDBCheckpointDiffer differ = rdbStore.getRocksDBCheckpointDiffer();
-    ReferenceCounted<OmSnapshot> snapDB1 = ozoneManager.getOmSnapshotManager()
+    UncheckedAutoCloseableSupplier<OmSnapshot> snapDB1 = ozoneManager.getOmSnapshotManager()
         .getActiveSnapshot(volumeName, bucketName, "snap1");
-    ReferenceCounted<OmSnapshot> snapDB2 = ozoneManager.getOmSnapshotManager()
+    UncheckedAutoCloseableSupplier<OmSnapshot> snapDB2 = ozoneManager.getOmSnapshotManager()
         .getActiveSnapshot(volumeName, bucketName, "snap2");
     DifferSnapshotInfo snap1 = getDifferSnapshotInfo(omMetadataManager,
         volumeName, bucketName, "snap1",
@@ -240,7 +240,7 @@ public void testDAGReconstruction()
 
     resp = store.createSnapshot(volumeName, bucketName, "snap3");
     LOG.debug("Snapshot created: {}", resp);
-    ReferenceCounted<OmSnapshot> snapDB3 = ozoneManager.getOmSnapshotManager()
+    UncheckedAutoCloseableSupplier<OmSnapshot> snapDB3 = ozoneManager.getOmSnapshotManager()
         .getActiveSnapshot(volumeName, bucketName, "snap3");
     DifferSnapshotInfo snap3 = getDifferSnapshotInfo(omMetadataManager,
         volumeName, bucketName, "snap3",

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/om/snapshot/TestSnapshotBackgroundServices.java

@@ -79,6 +79,7 @@
 import org.apache.ozone.test.LambdaTestUtils;
 import org.apache.ozone.test.tag.Flaky;
 import org.apache.ratis.server.protocol.TermIndex;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
@@ -260,7 +261,7 @@ public void testSnapshotAndKeyDeletionBackgroundServices()
 
     // get snapshot c
     OmSnapshot snapC;
-    try (ReferenceCounted<OmSnapshot> rcC = newLeaderOM
+    try (UncheckedAutoCloseableSupplier<OmSnapshot> rcC = newLeaderOM
         .getOmSnapshotManager()
         .getSnapshot(volumeName, bucketName, snapshotInfoC.getName())) {
       assertNotNull(rcC);
@@ -284,7 +285,7 @@ public void testSnapshotAndKeyDeletionBackgroundServices()
 
     // get snapshot d
     OmSnapshot snapD;
-    try (ReferenceCounted<OmSnapshot> rcD = newLeaderOM
+    try (UncheckedAutoCloseableSupplier<OmSnapshot> rcD = newLeaderOM
         .getOmSnapshotManager()
         .getSnapshot(volumeName, bucketName, snapshotInfoD.getName())) {
       assertNotNull(rcD);

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/om/snapshot/TestSnapshotDeletingServiceIntegrationTest.java

@@ -78,6 +78,7 @@
 import org.apache.hadoop.ozone.om.service.SnapshotDeletingService;
 import org.apache.ozone.test.GenericTestUtils;
 import org.apache.ozone.test.tag.Flaky;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeAll;
@@ -421,7 +422,7 @@ public void testSnapshotWithFSO() throws Exception {
     assertTableRowCount(renamedTable, 4);
     assertTableRowCount(deletedDirTable, 3);
 
-    ReferenceCounted<OmSnapshot> rcSnap1 =
+    UncheckedAutoCloseableSupplier<OmSnapshot> rcSnap1 =
         om.getOmSnapshotManager().getSnapshot(
             VOLUME_NAME, BUCKET_NAME_FSO, "snap1");
     OmSnapshot snap1 = rcSnap1.get();
@@ -613,8 +614,9 @@ public void testParallelExcecutionOfKeyDeletionAndSnapshotDeletion() throws Exce
     List<Table.KeyValue<String, String>> renamesKeyEntries;
     List<Table.KeyValue<String, List<OmKeyInfo>>> deletedKeyEntries;
     List<Table.KeyValue<String, OmKeyInfo>> deletedDirEntries;
-    try (ReferenceCounted<OmSnapshot> snapshot = om.getOmSnapshotManager().getSnapshot(testBucket.getVolumeName(),
-        testBucket.getName(), testBucket.getName() + "snap2")) {
+    try (UncheckedAutoCloseableSupplier<OmSnapshot> snapshot =
+             om.getOmSnapshotManager().getSnapshot(testBucket.getVolumeName(), testBucket.getName(),
+                 testBucket.getName() + "snap2")) {
       renamesKeyEntries = snapshot.get().getKeyManager().getRenamesKeyEntries(testBucket.getVolumeName(),
           testBucket.getName(), "", 1000);
       deletedKeyEntries = snapshot.get().getKeyManager().getDeletedKeyEntries(testBucket.getVolumeName(),
@@ -649,8 +651,9 @@ public void testParallelExcecutionOfKeyDeletionAndSnapshotDeletion() throws Exce
     Future<?> future = snapshotDeletingThread.submit(snapshotDeletionRunnable);
     GenericTestUtils.waitFor(snapshotDeletionStarted::get, 1000, 30000);
     future.get();
-    try (ReferenceCounted<OmSnapshot> snapshot = om.getOmSnapshotManager().getSnapshot(testBucket.getVolumeName(),
-        testBucket.getName(), testBucket.getName() + "snap2")) {
+    try (UncheckedAutoCloseableSupplier<OmSnapshot> snapshot =
+             om.getOmSnapshotManager().getSnapshot(testBucket.getVolumeName(), testBucket.getName(),
+                 testBucket.getName() + "snap2")) {
       Assertions.assertEquals(Collections.emptyList(),
           snapshot.get().getKeyManager().getRenamesKeyEntries(testBucket.getVolumeName(),
           testBucket.getName(), "", 1000));

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/OmMetadataManagerImpl.java

@@ -113,7 +113,6 @@
 import org.apache.hadoop.ozone.om.protocolPB.OzoneManagerProtocolClientSideTranslatorPB;
 import org.apache.hadoop.ozone.om.request.file.OMFileRequest;
 import org.apache.hadoop.ozone.om.request.util.OMMultipartUploadUtils;
-import org.apache.hadoop.ozone.om.snapshot.ReferenceCounted;
 import org.apache.hadoop.ozone.om.snapshot.SnapshotUtils;
 import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos.ExpiredMultipartUploadInfo;
 import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos.ExpiredMultipartUploadsBucket;
@@ -124,6 +123,7 @@
 import org.apache.hadoop.util.Time;
 import org.apache.ozone.compaction.log.CompactionLogEntry;
 import org.apache.ratis.util.ExitUtils;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.eclipse.jetty.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -1351,7 +1351,7 @@ public PendingKeysDeletion getPendingDeletionKeys(final int keyCount,
             continue;
           }
           // Get the latest snapshot in snapshot path.
-          try (ReferenceCounted<OmSnapshot> rcLatestSnapshot = previousSnapshotInfo == null ? null :
+          try (UncheckedAutoCloseableSupplier<OmSnapshot> rcLatestSnapshot = previousSnapshotInfo == null ? null :
               omSnapshotManager.getSnapshot(previousSnapshotInfo.getVolumeName(),
                   previousSnapshotInfo.getBucketName(), previousSnapshotInfo.getName())) {
 

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/OmSnapshotManager.java

@@ -92,7 +92,6 @@
 import org.apache.hadoop.ozone.om.helpers.SnapshotDiffJob;
 import org.apache.hadoop.ozone.om.helpers.SnapshotInfo;
 import org.apache.hadoop.ozone.om.service.SnapshotDiffCleanupService;
-import org.apache.hadoop.ozone.om.snapshot.ReferenceCounted;
 import org.apache.hadoop.ozone.om.snapshot.SnapshotCache;
 import org.apache.hadoop.ozone.om.snapshot.SnapshotDiffManager;
 import org.apache.hadoop.ozone.om.snapshot.SnapshotUtils;
@@ -102,6 +101,7 @@
 import org.apache.hadoop.ozone.snapshot.SnapshotDiffResponse;
 import org.apache.ozone.rocksdiff.RocksDBCheckpointDiffer;
 import org.apache.ratis.util.function.CheckedFunction;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.rocksdb.ColumnFamilyDescriptor;
 import org.rocksdb.ColumnFamilyHandle;
 import org.rocksdb.RocksDBException;
@@ -604,7 +604,7 @@ private static void deleteKeysFromDelKeyTableInSnapshotScope(
 
   // Get OmSnapshot if the keyName has ".snapshot" key indicator
   @SuppressWarnings("unchecked")
-  public ReferenceCounted<IOmMetadataReader> getActiveFsMetadataOrSnapshot(
+  public UncheckedAutoCloseableSupplier<IOmMetadataReader> getActiveFsMetadataOrSnapshot(
       String volumeName,
       String bucketName,
       String keyName) throws IOException {
@@ -622,28 +622,28 @@ public ReferenceCounted<IOmMetadataReader> getActiveFsMetadataOrSnapshot(
           bucketName), false, false);
       volumeName = resolvedBucket.realVolume();
       bucketName = resolvedBucket.realBucket();
-      return (ReferenceCounted<IOmMetadataReader>) (ReferenceCounted<?>)
+      return (UncheckedAutoCloseableSupplier<IOmMetadataReader>) (UncheckedAutoCloseableSupplier<?>)
           getActiveSnapshot(volumeName, bucketName, snapshotName);
     } else {
       return ozoneManager.getOmMetadataReader();
     }
   }
 
-  public ReferenceCounted<OmSnapshot> getActiveSnapshot(
+  public UncheckedAutoCloseableSupplier<OmSnapshot> getActiveSnapshot(
       String volumeName,
       String bucketName,
       String snapshotName) throws IOException {
     return getSnapshot(volumeName, bucketName, snapshotName, false);
   }
 
-  public ReferenceCounted<OmSnapshot> getSnapshot(
+  public UncheckedAutoCloseableSupplier<OmSnapshot> getSnapshot(
       String volumeName,
       String bucketName,
       String snapshotName) throws IOException {
     return getSnapshot(volumeName, bucketName, snapshotName, true);
   }
 
-  private ReferenceCounted<OmSnapshot> getSnapshot(
+  private UncheckedAutoCloseableSupplier<OmSnapshot> getSnapshot(
       String volumeName,
       String bucketName,
       String snapshotName,
@@ -659,7 +659,7 @@ private ReferenceCounted<OmSnapshot> getSnapshot(
     return getSnapshot(snapshotTableKey, skipActiveCheck);
   }
 
-  private ReferenceCounted<OmSnapshot> getSnapshot(String snapshotTableKey, boolean skipActiveCheck)
+  private UncheckedAutoCloseableSupplier<OmSnapshot> getSnapshot(String snapshotTableKey, boolean skipActiveCheck)
       throws IOException {
     SnapshotInfo snapshotInfo = SnapshotUtils.getSnapshotInfo(ozoneManager, snapshotTableKey);
     // Block FS API reads when snapshot is not active.
@@ -710,7 +710,7 @@ public static boolean areSnapshotChangesFlushedToDB(OMMetadataManager metadataMa
    * This should only be used for API calls initiated by background service e.g. purgeKeys, purgeSnapshot,
    * snapshotMoveDeletedKeys, and SetSnapshotProperty.
    */
-  public ReferenceCounted<OmSnapshot> getSnapshot(UUID snapshotId) throws IOException {
+  public UncheckedAutoCloseableSupplier<OmSnapshot> getSnapshot(UUID snapshotId) throws IOException {
     return snapshotCache.get(snapshotId);
   }
 

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/OzoneManager.java

@@ -283,7 +283,6 @@
 import org.apache.hadoop.ozone.om.service.OMRangerBGSyncService;
 import org.apache.hadoop.ozone.om.service.QuotaRepairTask;
 import org.apache.hadoop.ozone.om.snapshot.OmSnapshotUtils;
-import org.apache.hadoop.ozone.om.snapshot.ReferenceCounted;
 import org.apache.hadoop.ozone.om.upgrade.OMLayoutFeature;
 import org.apache.hadoop.ozone.om.upgrade.OMLayoutVersionManager;
 import org.apache.hadoop.ozone.om.upgrade.OMUpgradeFinalizer;
@@ -339,6 +338,7 @@
 import org.apache.ratis.util.ExitUtils;
 import org.apache.ratis.util.FileUtils;
 import org.apache.ratis.util.LifeCycle;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -490,9 +490,9 @@ public final class OzoneManager extends ServiceRuntimeInfoImpl
   private IAccessAuthorizer accessAuthorizer;
   // This metadata reader points to the active filesystem
   private OmMetadataReader omMetadataReader;
-  // Wrap active DB metadata reader in ReferenceCounted once to avoid
+  // Wrap active DB metadata reader in UncheckedAutoCloseableSupplier once to avoid
   // instance creation every single time.
-  private ReferenceCounted<IOmMetadataReader> rcOmMetadataReader;
+  private UncheckedAutoCloseableSupplier<IOmMetadataReader> rcOmMetadataReader;
   private OmSnapshotManager omSnapshotManager;
 
   @SuppressWarnings("methodlength")
@@ -963,7 +963,17 @@ private void instantiateServices(boolean withNewSnapshot) throws IOException {
         this, LOG, AUDIT, metrics, accessAuthorizer);
     // Active DB's OmMetadataReader instance does not need to be reference
     // counted, but it still needs to be wrapped to be consistent.
-    rcOmMetadataReader = new ReferenceCounted<>(omMetadataReader, true, null);
+    rcOmMetadataReader = new UncheckedAutoCloseableSupplier<IOmMetadataReader>() {
+      @Override
+      public IOmMetadataReader get() {
+        return omMetadataReader;
+      }
+
+      @Override
+      public void close() {
+
+      }
+    };
 
     // Reload snapshot feature config flag
     fsSnapshotEnabled = configuration.getBoolean(
@@ -2714,7 +2724,7 @@ public boolean getAllowListAllVolumes() {
     return allowListAllVolumes;
   }
 
-  public ReferenceCounted<IOmMetadataReader> getOmMetadataReader() {
+  public UncheckedAutoCloseableSupplier<IOmMetadataReader> getOmMetadataReader() {
     return rcOmMetadataReader;
   }
 
@@ -2984,7 +2994,7 @@ public OmBucketInfo getBucketInfo(String volume, String bucket)
    */
   @Override
   public OmKeyInfo lookupKey(OmKeyArgs args) throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader = getReader(args)) {
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader = getReader(args)) {
       return rcReader.get().lookupKey(args);
     }
   }
@@ -2996,7 +3006,7 @@ public OmKeyInfo lookupKey(OmKeyArgs args) throws IOException {
   public KeyInfoWithVolumeContext getKeyInfo(final OmKeyArgs args,
                                              boolean assumeS3Context)
       throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader = getReader(args)) {
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader = getReader(args)) {
       return rcReader.get().getKeyInfo(args, assumeS3Context);
     }
   }
@@ -3008,7 +3018,7 @@ public KeyInfoWithVolumeContext getKeyInfo(final OmKeyArgs args,
   public ListKeysResult listKeys(String volumeName, String bucketName,
                                  String startKey, String keyPrefix, int maxKeys)
       throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader =
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader =
              getReader(volumeName, bucketName, keyPrefix)) {
       return rcReader.get().listKeys(
           volumeName, bucketName, startKey, keyPrefix, maxKeys);
@@ -3841,7 +3851,7 @@ public OmMultipartUploadList listMultipartUploads(String volumeName,
    */
   @Override
   public OzoneFileStatus getFileStatus(OmKeyArgs args) throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader =
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader =
         getReader(args)) {
       return rcReader.get().getFileStatus(args);
     }
@@ -3852,7 +3862,7 @@ public OzoneFileStatus getFileStatus(OmKeyArgs args) throws IOException {
    */
   @Override
   public OmKeyInfo lookupFile(OmKeyArgs args) throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader =
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader =
         getReader(args)) {
       return rcReader.get().lookupFile(args);
     }
@@ -3872,7 +3882,7 @@ public List<OzoneFileStatus> listStatus(OmKeyArgs args, boolean recursive,
   public List<OzoneFileStatus> listStatus(OmKeyArgs args, boolean recursive,
       String startKey, long numEntries, boolean allowPartialPrefixes)
       throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader =
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader =
         getReader(args)) {
       return rcReader.get().listStatus(
           args, recursive, startKey, numEntries, allowPartialPrefixes);
@@ -3896,7 +3906,7 @@ public List<OzoneFileStatusLight> listStatusLight(OmKeyArgs args,
    */
   @Override
   public List<OzoneAcl> getAcl(OzoneObj obj) throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader =
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader =
         getReader(obj)) {
       return rcReader.get().getAcl(obj);
     }
@@ -4860,7 +4870,7 @@ public void startQuotaRepair(List<String> buckets) throws IOException {
   @Override
   public Map<String, String> getObjectTagging(final OmKeyArgs args)
       throws IOException {
-    try (ReferenceCounted<IOmMetadataReader> rcReader = getReader(args)) {
+    try (UncheckedAutoCloseableSupplier<IOmMetadataReader> rcReader = getReader(args)) {
       return rcReader.get().getObjectTagging(args);
     }
   }
@@ -4947,9 +4957,9 @@ public static HddsProtos.OzoneManagerDetailsProto getOmDetailsProto(
    * Caller is responsible of closing the return value.
    * Using try-with-resources is recommended.
    * @param keyArgs OmKeyArgs
-   * @return ReferenceCounted<IOmMetadataReader, SnapshotCache>
+   * @return UncheckedAutoCloseableSupplier<IOmMetadataReader, SnapshotCache>
    */
-  private ReferenceCounted<IOmMetadataReader> getReader(OmKeyArgs keyArgs)
+  private UncheckedAutoCloseableSupplier<IOmMetadataReader> getReader(OmKeyArgs keyArgs)
       throws IOException {
     return omSnapshotManager.getActiveFsMetadataOrSnapshot(
         keyArgs.getVolumeName(), keyArgs.getBucketName(), keyArgs.getKeyName());
@@ -4962,9 +4972,9 @@ private ReferenceCounted<IOmMetadataReader> getReader(OmKeyArgs keyArgs)
    * @param volumeName volume name
    * @param bucketName bucket name
    * @param key key path
-   * @return ReferenceCounted<IOmMetadataReader, SnapshotCache>
+   * @return UncheckedAutoCloseableSupplier<IOmMetadataReader, SnapshotCache>
    */
-  private ReferenceCounted<IOmMetadataReader> getReader(
+  private UncheckedAutoCloseableSupplier<IOmMetadataReader> getReader(
           String volumeName, String bucketName, String key) throws IOException {
     return omSnapshotManager.getActiveFsMetadataOrSnapshot(
         volumeName, bucketName, key);
@@ -4975,9 +4985,9 @@ private ReferenceCounted<IOmMetadataReader> getReader(
    * Caller is responsible of closing the return value.
    * Using try-with-resources is recommended.
    * @param ozoneObj OzoneObj
-   * @return ReferenceCounted<IOmMetadataReader, SnapshotCache>
+   * @return UncheckedAutoCloseableSupplier<IOmMetadataReader, SnapshotCache>
    */
-  private ReferenceCounted<IOmMetadataReader> getReader(OzoneObj ozoneObj)
+  private UncheckedAutoCloseableSupplier<IOmMetadataReader> getReader(OzoneObj ozoneObj)
       throws IOException {
     return omSnapshotManager.getActiveFsMetadataOrSnapshot(
         ozoneObj.getVolumeName(),

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/SstFilteringService.java

@@ -46,7 +46,7 @@
 import org.apache.hadoop.ozone.om.exceptions.OMException;
 import org.apache.hadoop.ozone.om.helpers.SnapshotInfo;
 import org.apache.hadoop.ozone.om.lock.OMLockDetails;
-import org.apache.hadoop.ozone.om.snapshot.ReferenceCounted;
+import org.apache.ratis.util.function.UncheckedAutoCloseableSupplier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -190,7 +190,7 @@ public BackgroundTaskResult call() throws Exception {
                     snapshotInfo.getBucketName());
 
             try (
-                ReferenceCounted<OmSnapshot> snapshotMetadataReader =
+                UncheckedAutoCloseableSupplier<OmSnapshot> snapshotMetadataReader =
                     snapshotManager.get().getActiveSnapshot(
                         snapshotInfo.getVolumeName(),
                         snapshotInfo.getBucketName(),