Improve ShardedDOMDataTreeWriteTransaction performance
[mdsal.git] / dom / mdsal-dom-broker / src / main / java / org / opendaylight / mdsal / dom / broker / ShardedDOMDataTreeProducer.java
index 241f3d993127d48af696c2fb32195322bc0c74c0..b19d956192f23abd9f992b075a98fd272e1c0678 100644 (file)
@@ -8,18 +8,20 @@
 package org.opendaylight.mdsal.dom.broker;
 
 import com.google.common.base.Preconditions;
+import com.google.common.base.Verify;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.BiMap;
+import com.google.common.collect.Collections2;
 import com.google.common.collect.ImmutableBiMap;
 import com.google.common.collect.ImmutableBiMap.Builder;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Multimap;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
+import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
 import javax.annotation.concurrent.GuardedBy;
 import org.opendaylight.mdsal.dom.api.DOMDataTreeCursorAwareTransaction;
 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
@@ -29,21 +31,39 @@ import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerException;
 import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
 import org.opendaylight.mdsal.dom.store.inmemory.DOMDataTreeShardProducer;
 import org.opendaylight.mdsal.dom.store.inmemory.WriteableDOMDataTreeShard;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
     private static final Logger LOG = LoggerFactory.getLogger(ShardedDOMDataTreeProducer.class);
+
     private final Set<DOMDataTreeIdentifier> subtrees;
     private final ShardedDOMDataTree dataTree;
 
     private BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducer = ImmutableBiMap.of();
     private Map<DOMDataTreeIdentifier, DOMDataTreeShard> idToShard;
 
+    private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+        CURRENT_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+            ShardedDOMDataTreeWriteTransaction.class, "currentTx");
+    @SuppressWarnings("unused")
+    private volatile ShardedDOMDataTreeWriteTransaction currentTx;
+
+    private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+        OPEN_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+            ShardedDOMDataTreeWriteTransaction.class, "openTx");
+    private volatile ShardedDOMDataTreeWriteTransaction openTx;
+
+    private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+        LAST_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+            ShardedDOMDataTreeWriteTransaction.class, "lastTx");
+    private volatile ShardedDOMDataTreeWriteTransaction lastTx;
+
     @GuardedBy("this")
-    private DOMDataTreeCursorAwareTransaction openTx;
+    private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = ImmutableMap.of();
     @GuardedBy("this")
-    private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = Collections.emptyMap();
+    private Set<YangInstanceIdentifier> childRoots = ImmutableSet.of();
     @GuardedBy("this")
     private boolean closed;
 
@@ -85,12 +105,14 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
         idToShard = ImmutableMap.copyOf(shardMap);
     }
 
-    private BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> mapIdsToProducer(final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
+    private static BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> mapIdsToProducer(
+            final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
         final Builder<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducerBuilder = ImmutableBiMap.builder();
         for (final Entry<DOMDataTreeShard, Collection<DOMDataTreeIdentifier>> entry : shardToId.asMap().entrySet()) {
             if (entry.getKey() instanceof WriteableDOMDataTreeShard) {
                 //create a single producer for all prefixes in a single shard
-                final DOMDataTreeShardProducer producer = ((WriteableDOMDataTreeShard) entry.getKey()).createProducer(entry.getValue());
+                final DOMDataTreeShardProducer producer = ((WriteableDOMDataTreeShard) entry.getKey())
+                        .createProducer(entry.getValue());
                 // id mapped to producers
                 for (final DOMDataTreeIdentifier id : entry.getValue()) {
                     idToProducerBuilder.put(id, producer);
@@ -108,9 +130,34 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
         Preconditions.checkState(!closed, "Producer is already closed");
         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
 
-        this.openTx = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, children);
+        LOG.debug("Creating transaction from producer");
+        final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
+        final ShardedDOMDataTreeWriteTransaction ret;
+        if (isolated) {
+            // Isolated case. If we have a previous transaction, submit it before returning this one.
+            if (current != null) {
+                submitTransaction(current);
+            }
+            ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, childRoots);
+        } else {
+            // Non-isolated case, see if we can reuse the transaction
+            if (current != null) {
+                LOG.debug("Reusing previous transaction {} since there is still a transaction inflight",
+                        current.getIdentifier());
+                ret = current;
+            } else {
+                ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, childRoots);
+            }
+        }
+
+        final boolean success = OPEN_UPDATER.compareAndSet(this, null, ret);
+        Verify.verify(success);
+        return ret;
+    }
 
-        return openTx;
+    private void submitTransaction(final ShardedDOMDataTreeWriteTransaction current) {
+        lastTx = current;
+        current.doSubmit(this::transactionSuccessful, this::transactionFailed);
     }
 
     @GuardedBy("this")
@@ -125,9 +172,9 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
     }
 
     @GuardedBy("this")
-    private DOMDataTreeProducer lookupChild(final DOMDataTreeIdentifier s) {
+    private DOMDataTreeProducer lookupChild(final DOMDataTreeIdentifier domDataTreeIdentifier) {
         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeProducer> e : children.entrySet()) {
-            if (e.getKey().contains(s)) {
+            if (e.getKey().contains(domDataTreeIdentifier)) {
                 return e.getValue();
             }
         }
@@ -150,7 +197,8 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
             // Check if part of the requested subtree is not delegated to a child.
             for (final DOMDataTreeIdentifier c : children.keySet()) {
                 if (s.contains(c)) {
-                    throw new IllegalArgumentException(String.format("Subtree %s cannot be delegated as it is superset of already-delegated %s", s, c));
+                    throw new IllegalArgumentException(String.format("Subtree %s cannot be delegated as it is"
+                            + " superset of already-delegated %s", s, c));
                 }
             }
         }
@@ -163,6 +211,8 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
         }
 
         children = cb.build();
+        childRoots = ImmutableSet.copyOf(Collections2.transform(children.keySet(),
+            DOMDataTreeIdentifier::getRootIdentifier));
         return ret;
     }
 
@@ -192,25 +242,62 @@ class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
         return subtrees;
     }
 
-    synchronized void cancelTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
-        if (!openTx.equals(transaction)) {
+    void cancelTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
+        final boolean success = OPEN_UPDATER.compareAndSet(this, transaction, null);
+        if (success) {
+            LOG.debug("Transaction {} cancelled", transaction);
+        } else {
             LOG.warn("Transaction {} is not open in producer {}", transaction, this);
-            return;
         }
+    }
+
+    void processTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
+        final boolean wasOpen = OPEN_UPDATER.compareAndSet(this, transaction, null);
+        Verify.verify(wasOpen);
 
-        LOG.debug("Transaction {} cancelled", transaction);
-        openTx = null;
+        if (lastTx != null) {
+            final boolean success = CURRENT_UPDATER.compareAndSet(this, null, transaction);
+            Verify.verify(success);
+            if (lastTx == null) {
+                // Dispatch after requeue
+                processCurrentTransaction();
+            }
+        } else {
+            submitTransaction(transaction);
+        }
+    }
+
+    void transactionSuccessful(final ShardedDOMDataTreeWriteTransaction tx) {
+        LOG.debug("Transaction {} completed successfully", tx.getIdentifier());
+
+        tx.onTransactionSuccess(null);
+        processNextTransaction(tx);
+    }
+
+    void transactionFailed(final ShardedDOMDataTreeWriteTransaction tx, final Throwable throwable) {
+        LOG.debug("Transaction {} failed", tx.getIdentifier(), throwable);
+
+        tx.onTransactionFailure(throwable);
+        processNextTransaction(tx);
+    }
+
+    private void processCurrentTransaction() {
+        final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
+        if (current != null) {
+            submitTransaction(current);
+        }
     }
 
-    synchronized void transactionSubmitted(final ShardedDOMDataTreeWriteTransaction transaction) {
-        Preconditions.checkState(openTx.equals(transaction));
-        openTx = null;
+    private synchronized void processNextTransaction(final ShardedDOMDataTreeWriteTransaction tx) {
+        final boolean wasLast = LAST_UPDATER.compareAndSet(this, tx, null);
+        if (wasLast) {
+            processCurrentTransaction();
+        }
     }
 
     synchronized void boundToListener(final ShardedDOMDataTreeListenerContext<?> listener) {
-        // FIXME: Add option to dettach
-        Preconditions.checkState(this.attachedListener == null,
-                "Producer %s is already attached to other listener.",
+        // FIXME: Add option to detach
+        Preconditions.checkState(this.attachedListener == null, "Producer %s is already attached to other listener.",
                 listener.getListener());
         this.attachedListener = listener;
     }