BUG-8618: eliminate SimpleShardDataTreeCohort subclasses
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / ShardDataTree.java
index cf90b0be1009525c7beeaea0e2981b1cc4f1a298..27577b27d8d4f9342a90ed6db72ec2a5ca70c06c 100644 (file)
@@ -14,7 +14,6 @@ import com.google.common.base.MoreObjects;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Stopwatch;
-import com.google.common.base.Ticker;
 import com.google.common.base.Verify;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
@@ -44,6 +43,7 @@ import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifie
 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
 import org.opendaylight.controller.cluster.datastore.DataTreeCohortActorRegistry.CohortRegistryCommand;
 import org.opendaylight.controller.cluster.datastore.ShardDataTreeCohort.State;
+import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats;
 import org.opendaylight.controller.cluster.datastore.persisted.AbortTransactionPayload;
 import org.opendaylight.controller.cluster.datastore.persisted.AbstractIdentifiablePayload;
 import org.opendaylight.controller.cluster.datastore.persisted.CloseLocalHistoryPayload;
@@ -180,8 +180,8 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
         return logContext;
     }
 
-    final Ticker ticker() {
-        return shard.ticker();
+    final long readTime() {
+        return shard.ticker().read();
     }
 
     public TipProducingDataTree getDataTree() {
@@ -520,12 +520,15 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
         return ret;
     }
 
-    ShardDataTreeTransactionChain ensureTransactionChain(final LocalHistoryIdentifier historyId) {
+    ShardDataTreeTransactionChain ensureTransactionChain(final LocalHistoryIdentifier historyId,
+            @Nullable final Runnable callback) {
         ShardDataTreeTransactionChain chain = transactionChains.get(historyId);
         if (chain == null) {
             chain = new ShardDataTreeTransactionChain(historyId, this);
             transactionChains.put(historyId, chain);
-            replicatePayload(historyId, CreateLocalHistoryPayload.create(historyId), null);
+            replicatePayload(historyId, CreateLocalHistoryPayload.create(historyId), callback);
+        } else if (callback != null) {
+            callback.run();
         }
 
         return chain;
@@ -536,7 +539,7 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
             return new ReadOnlyShardDataTreeTransaction(this, txId, dataTree.takeSnapshot());
         }
 
-        return ensureTransactionChain(txId.getHistoryId()).newReadOnlyTransaction(txId);
+        return ensureTransactionChain(txId.getHistoryId(), null).newReadOnlyTransaction(txId);
     }
 
     ReadWriteShardDataTreeTransaction newReadWriteTransaction(final TransactionIdentifier txId) {
@@ -545,7 +548,7 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
                     .newModification());
         }
 
-        return ensureTransactionChain(txId.getHistoryId()).newReadWriteTransaction(txId);
+        return ensureTransactionChain(txId.getHistoryId(), null).newReadWriteTransaction(txId);
     }
 
     @VisibleForTesting
@@ -670,24 +673,6 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
         return dataTree.takeSnapshot().newModification();
     }
 
-    /**
-     * Commits a modification.
-     *
-     * @deprecated This method violates DataTree containment and will be removed.
-     */
-    @VisibleForTesting
-    @Deprecated
-    public DataTreeCandidate commit(final DataTreeModification modification) throws DataValidationFailedException {
-        // Direct modification commit is a utility, which cannot be used while we have transactions in-flight
-        Preconditions.checkState(tip == dataTree, "Cannot modify data tree while transacgitons are pending");
-
-        modification.ready();
-        dataTree.validate(modification);
-        DataTreeCandidate candidate = dataTree.prepare(modification);
-        dataTree.commit(candidate);
-        return candidate;
-    }
-
     public Collection<ShardDataTreeCohort> getAndClearPendingTransactions() {
         Collection<ShardDataTreeCohort> ret = new ArrayList<>(getQueueSize());
 
@@ -734,12 +719,10 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
             LOG.debug("{}: Validating transaction {}", logContext, cohort.getIdentifier());
             Exception cause;
             try {
-                cohort.throwCanCommitFailure();
-
                 tip.validate(modification);
                 LOG.debug("{}: Transaction {} validated", logContext, cohort.getIdentifier());
                 cohort.successfulCanCommit();
-                entry.lastAccess = ticker().read();
+                entry.lastAccess = readTime();
                 return;
             } catch (ConflictingModificationAppliedException e) {
                 LOG.warn("{}: Store Tx {}: Conflicting modification for path {}.", logContext, cohort.getIdentifier(),
@@ -802,8 +785,12 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
     }
 
     void startCanCommit(final SimpleShardDataTreeCohort cohort) {
-        final SimpleShardDataTreeCohort current = pendingTransactions.peek().cohort;
-        if (!cohort.equals(current)) {
+        final CommitEntry head = pendingTransactions.peek();
+        if (head == null) {
+            LOG.warn("{}: No transactions enqueued while attempting to start canCommit on {}", logContext, cohort);
+            return;
+        }
+        if (!cohort.equals(head.cohort)) {
             LOG.debug("{}: Transaction {} scheduled for canCommit step", logContext, cohort.getIdentifier());
             return;
         }
@@ -839,7 +826,7 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
         // Set the tip of the data tree.
         tip = Verify.verifyNotNull(candidate);
 
-        entry.lastAccess = ticker().read();
+        entry.lastAccess = readTime();
 
         pendingTransactions.remove();
         pendingCommits.add(entry);
@@ -953,17 +940,16 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
     @Override
     ShardDataTreeCohort createFailedCohort(final TransactionIdentifier txId, final DataTreeModification mod,
             final Exception failure) {
-        SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort.DeadOnArrival(this, mod, txId, failure);
-        pendingTransactions.add(new CommitEntry(cohort, ticker().read()));
+        final SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort(this, mod, txId, failure);
+        pendingTransactions.add(new CommitEntry(cohort, readTime()));
         return cohort;
     }
 
     @Override
-    ShardDataTreeCohort createReadyCohort(final TransactionIdentifier txId,
-            final DataTreeModification mod) {
-        SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort.Normal(this, mod, txId,
+    ShardDataTreeCohort createReadyCohort(final TransactionIdentifier txId, final DataTreeModification mod) {
+        SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort(this, mod, txId,
                 cohortRegistry.createCohort(schemaContext, txId, COMMIT_STEP_TIMEOUT));
-        pendingTransactions.add(new CommitEntry(cohort, ticker().read()));
+        pendingTransactions.add(new CommitEntry(cohort, readTime()));
         return cohort;
     }
 
@@ -974,33 +960,37 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
             return createReadyCohort(txId, mod);
         }
 
-        return ensureTransactionChain(txId.getHistoryId()).createReadyCohort(txId, mod);
+        return ensureTransactionChain(txId.getHistoryId(), null).createReadyCohort(txId, mod);
     }
 
     @SuppressFBWarnings(value = "DB_DUPLICATE_SWITCH_CLAUSES", justification = "See inline comments below.")
     void checkForExpiredTransactions(final long transactionCommitTimeoutMillis) {
         final long timeout = TimeUnit.MILLISECONDS.toNanos(transactionCommitTimeoutMillis);
-        final long now = ticker().read();
+        final long now = readTime();
 
         final Queue<CommitEntry> currentQueue = !pendingFinishCommits.isEmpty() ? pendingFinishCommits :
             !pendingCommits.isEmpty() ? pendingCommits : pendingTransactions;
         final CommitEntry currentTx = currentQueue.peek();
         if (currentTx != null && currentTx.lastAccess + timeout < now) {
+            final State state = currentTx.cohort.getState();
             LOG.warn("{}: Current transaction {} has timed out after {} ms in state {}", logContext,
-                    currentTx.cohort.getIdentifier(), transactionCommitTimeoutMillis, currentTx.cohort.getState());
+                    currentTx.cohort.getIdentifier(), transactionCommitTimeoutMillis, state);
             boolean processNext = true;
-            switch (currentTx.cohort.getState()) {
+            final TimeoutException cohortFailure = new TimeoutException("Backend timeout in state " + state + " after "
+                    + transactionCommitTimeoutMillis + "ms");
+
+            switch (state) {
                 case CAN_COMMIT_PENDING:
-                    currentQueue.remove().cohort.failedCanCommit(new TimeoutException());
+                    currentQueue.remove().cohort.failedCanCommit(cohortFailure);
                     break;
                 case CAN_COMMIT_COMPLETE:
                     // The suppression of the FindBugs "DB_DUPLICATE_SWITCH_CLAUSES" warning pertains to this clause
                     // whose code is duplicated with PRE_COMMIT_COMPLETE. The clauses aren't combined in case the code
                     // in PRE_COMMIT_COMPLETE is changed.
-                    currentQueue.remove().cohort.reportFailure(new TimeoutException());
+                    currentQueue.remove().cohort.reportFailure(cohortFailure);
                     break;
                 case PRE_COMMIT_PENDING:
-                    currentQueue.remove().cohort.failedPreCommit(new TimeoutException());
+                    currentQueue.remove().cohort.failedPreCommit(cohortFailure);
                     break;
                 case PRE_COMMIT_COMPLETE:
                     // FIXME: this is a legacy behavior problem. Three-phase commit protocol specifies that after we
@@ -1020,7 +1010,7 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
                     //        In order to make the pre-commit timer working across failovers, though, we need
                     //        a per-shard cluster-wide monotonic time, so a follower becoming the leader can accurately
                     //        restart the timer.
-                    currentQueue.remove().cohort.reportFailure(new TimeoutException());
+                    currentQueue.remove().cohort.reportFailure(cohortFailure);
                     break;
                 case COMMIT_PENDING:
                     LOG.warn("{}: Transaction {} is still committing, cannot abort", logContext,
@@ -1028,10 +1018,12 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
                     currentTx.lastAccess = now;
                     processNext = false;
                     return;
+                case READY:
+                    currentQueue.remove().cohort.reportFailure(cohortFailure);
+                    break;
                 case ABORTED:
                 case COMMITTED:
                 case FAILED:
-                case READY:
                 default:
                     currentQueue.remove();
             }
@@ -1137,4 +1129,8 @@ public class ShardDataTree extends ShardDataTreeTransactionParent {
             runOnPendingTransactionsComplete = null;
         }
     }
+
+    ShardStats getStats() {
+        return shard.getShardMBean();
+    }
 }