OAK-6227: There should be a way to retrieve oldest timestamp to keep …

…from nodestores

Simplify checkpoint mbean method - expose 2 methods now: one for timestamp and another for human redable date

OAK-2808: Active deletion of 'deleted' Lucene index files from DataStore without relying on full scale Blob GC

Refactor wrt change in checkpoint mbean method simplification. Also minor change to not flush files if there were no blobs that were deleted.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1797778 13f79535-47bb-0310-9956-ffa450edef68

oak-api/src/main/java/org/apache/jackrabbit/oak/api/jmx/CheckpointMBean.java

@@ -19,11 +19,12 @@
 
 package org.apache.jackrabbit.oak.api.jmx;
 
-import javax.management.openmbean.CompositeData;
 import javax.management.openmbean.TabularData;
 
 import aQute.bnd.annotation.ProviderType;
 
+import java.util.Date;
+
 /**
  * MBean for managing {@code org.apache.jackrabbit.oak.spi.state.NodeStore#checkpoint checkpoints}.
  */
@@ -39,9 +40,14 @@ public interface CheckpointMBean {
     TabularData listCheckpoints();
 
     /**
-     * @return creation information about oldest checkpoint.
+     * @return creation timestamp of oldest checkpoint.
+     */
+    long getOldestCheckpointCreationTimestamp();
+
+    /**
+     * @return creation date of oldest checkpoint.
      */
-    CompositeData getOldestCheckpointCreationTime();
+    Date getOldestCheckpointCreationDate();
 
     /**
      * Create a new checkpoint with the given {@code lifetime}.

oak-core-spi/src/main/java/org/apache/jackrabbit/oak/commons/jmx/AbstractCheckpointMBean.java

@@ -26,17 +26,14 @@
 import java.util.Map.Entry;
 
 import javax.management.openmbean.ArrayType;
-import javax.management.openmbean.CompositeData;
 import javax.management.openmbean.CompositeDataSupport;
 import javax.management.openmbean.CompositeType;
 import javax.management.openmbean.OpenDataException;
 import javax.management.openmbean.OpenType;
-import javax.management.openmbean.SimpleType;
 import javax.management.openmbean.TabularData;
 import javax.management.openmbean.TabularDataSupport;
 import javax.management.openmbean.TabularType;
 
-import com.google.common.collect.Maps;
 import org.apache.jackrabbit.oak.api.jmx.CheckpointMBean;
 
 /**
@@ -94,24 +91,12 @@ public TabularData listCheckpoints() {
         }
     }
 
-    protected abstract long getOldestCheckpointCreationTimestamp();
+    @Override
+    public abstract long getOldestCheckpointCreationTimestamp();
 
     @Override
-    public CompositeData getOldestCheckpointCreationTime() {
-        try {
-            Map<String, Object> values = Maps.newHashMap();
-            long timestamp = getOldestCheckpointCreationTimestamp();
-            values.put("timestamp", timestamp);
-            values.put("time", new Date(timestamp));
-            CompositeDataSupport csd = new CompositeDataSupport(
-              new CompositeType("OldestCheckpointTime", "Creation time of oldest checkpoint",
-                      new String[]{"timestamp", "time"}, new String[]{"epoch timestamp", "human readable date"},
-                      new OpenType[]{SimpleType.LONG, SimpleType.DATE}), values);
-
-            return csd;
-        } catch (OpenDataException e) {
-            throw new IllegalStateException(e);
-        }
+    public Date getOldestCheckpointCreationDate() {
+        return new Date(getOldestCheckpointCreationTimestamp());
     }
 
     /**

oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/document/DocumentCheckpointMBean.java

@@ -55,7 +55,7 @@ protected void collectCheckpoints(TabularDataSupport tab) throws OpenDataExcepti
     }
 
     @Override
-    protected long getOldestCheckpointCreationTimestamp() {
+    public long getOldestCheckpointCreationTimestamp() {
         Map<Revision, Info> checkpoints = store.getCheckpoints().getCheckpoints();
 
         long minTimestamp = Long.MAX_VALUE;

oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/LuceneIndexProviderService.java

@@ -34,7 +34,6 @@
 
 import javax.annotation.Nonnull;
 import javax.management.NotCompliantMBeanException;
-import javax.management.openmbean.CompositeData;
 
 import com.google.common.base.Strings;
 import com.google.common.collect.Lists;
@@ -736,21 +735,11 @@ private void initializeActiveBlobCollector(Whiteboard whiteboard, Map<String, ?>
     private long getSafeTimestampForDeletedBlobs(CheckpointMBean checkpointMBean) {
         long timestamp = clock.getTime() - TimeUnit.SECONDS.toMillis(MIN_BLOB_AGE_TO_ACTIVELY_DELETE);
 
-        CompositeData data = checkpointMBean.getOldestCheckpointCreationTime();
-        Object timestampObj = data.get("timestamp");
-        String timestampStr = null;
-        if (timestampObj != null) {
-            timestampStr = timestampObj.toString();
-        }
-        try {
-            long minCheckpointTimestamp = Long.parseLong(timestampStr);
-            if (minCheckpointTimestamp < timestamp) {
-                log.info("Oldest checkpoint time data ({}) is older than buffer period for deleted blobs." +
-                        " Using that instead", data);
-                timestamp = minCheckpointTimestamp;
-            }
-        } catch (NumberFormatException nfe) {
-            log.warn("Couldn't find timestamp in checkpoint mbean output: {}", data);
+        long minCheckpointTimestamp = checkpointMBean.getOldestCheckpointCreationTimestamp();
+        if (minCheckpointTimestamp < timestamp) {
+            log.info("Oldest checkpoint timestamp ({}) is older than buffer period ({}) for deleted blobs." +
+                    " Using that instead", minCheckpointTimestamp, timestamp);
+            timestamp = minCheckpointTimestamp;
         }
 
         return timestamp;

oak-lucene/src/main/java/org/apache/jackrabbit/oak/plugins/index/lucene/directory/ActiveDeletedBlobCollectorFactory.java

@@ -315,13 +315,15 @@ private synchronized void flushDeletedBlobs() {
                 while (deletedBlobs.peek() != null) {
                     localDeletedBlobs.add(deletedBlobs.poll());
                 }
-                File outFile = new File(rootDirectory, getBlobFileName());
-                try {
-                    long start = PERF_LOG.start();
-                    FileUtils.writeLines(outFile, localDeletedBlobs, true);
-                    PERF_LOG.end(start, 1, "Flushing deleted blobs");
-                } catch (IOException e) {
-                    LOG.error("Couldn't write out to " + outFile, e);
+                if (localDeletedBlobs.size() > 0) {
+                    File outFile = new File(rootDirectory, getBlobFileName());
+                    try {
+                        long start = PERF_LOG.start();
+                        FileUtils.writeLines(outFile, localDeletedBlobs, true);
+                        PERF_LOG.end(start, 1, "Flushing deleted blobs");
+                    } catch (IOException e) {
+                        LOG.error("Couldn't write out to " + outFile, e);
+                    }
                 }
             }
 

oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/SegmentCheckpointMBean.java

@@ -52,7 +52,7 @@ protected void collectCheckpoints(TabularDataSupport tab) throws OpenDataExcepti
     }
 
     @Override
-    protected long getOldestCheckpointCreationTimestamp() {
+    public long getOldestCheckpointCreationTimestamp() {
         long minTimestamp = Long.MAX_VALUE;
         for (ChildNodeEntry cne : store.getCheckpoints().getChildNodeEntries()) {
             NodeState checkpoint = cne.getNodeState();