nizhikov commented on code in PR #10314: URL: https://github.com/apache/ignite/pull/10314#discussion_r1030463126
########## modules/core/src/main/java/org/apache/ignite/internal/processors/cache/consistentcut/ConsistentCutManager.java: ########## @@ -0,0 +1,194 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.ignite.internal.processors.cache.consistentcut; + +import java.util.Objects; +import java.util.UUID; +import java.util.concurrent.atomic.AtomicReference; +import org.apache.ignite.IgniteCheckedException; +import org.apache.ignite.internal.pagemem.wal.record.ConsistentCutFinishRecord; +import org.apache.ignite.internal.processors.cache.GridCacheMessage; +import org.apache.ignite.internal.processors.cache.GridCacheSharedContext; +import org.apache.ignite.internal.processors.cache.GridCacheSharedManagerAdapter; +import org.apache.ignite.internal.processors.cache.distributed.dht.preloader.GridDhtPartitionsExchangeFuture; +import org.apache.ignite.internal.processors.cache.distributed.dht.preloader.PartitionsExchangeAware; +import org.apache.ignite.internal.processors.cache.transactions.IgniteInternalTx; +import org.apache.ignite.internal.processors.cache.transactions.IgniteTxAdapter; +import org.apache.ignite.internal.processors.cache.transactions.IgniteTxManager; +import org.apache.ignite.internal.util.tostring.GridToStringInclude; +import org.jetbrains.annotations.Nullable; + +import static org.apache.ignite.internal.processors.cache.GridCacheUtils.baselineNode; + +/** + * Processes all stuff related to Consistent Cut. + * <p> + * Consistent Cut is a distributed algorithm that defines two set of transactions - BEFORE and AFTER cut - on baseline nodes. + * It guarantees that every transaction was included into BEFORE on one node also included into the BEFORE on every other node + * participated in the transaction. It means that Ignite nodes can safely recover themselves to the consistent BEFORE + * state without any coordination with each other. + * <p> + * The algorithm starts on Ignite node by snapshot creation command. Other nodes are notified with discovery message of snapshot + * distributed process or by transaction messages {@link ConsistentCutAwareMessage}. + * <p> + * The algorithm consist of steps: + * 1. On receiving new Consistent Cut ID it immediately creates new {@link ConsistentCut} before processing the message. + * 2. It starts wrapping all transaction messages to {@link ConsistentCutAwareMessage}. + * 3. Every transaction holds {@link IgniteTxAdapter#cutId()} after which it committed. The value is initially set on + * originated node for two-phase-commit, and backup node for one-phase-commit. Then it is propagated to other nodes with + * {@link ConsistentCutAwareMessage}. + * 4. On baseline nodes it awaits {@link BaselineConsistentCut}, that completes with pointer to {@link ConsistentCutFinishRecord}. + * 5. After Consistent Cut finished on all nodes, it clears {@link ConsistentCut} and stops wrapping messages. + */ +public class ConsistentCutManager extends GridCacheSharedManagerAdapter implements PartitionsExchangeAware { + /** Current Consistent Cut, {@code null} if not running. */ + @GridToStringInclude + private final AtomicReference<ConsistentCut> consistentCutRef = new AtomicReference<>(); + + /** ID of the last finished Consistent Cut. Required to avoid re-run Consistent Cut with the same id. */ + @GridToStringInclude + protected volatile UUID lastFinishedCutId; + + /** {@inheritDoc} */ + @Override public void start0() throws IgniteCheckedException { + super.start0(); + + cctx.exchange().registerExchangeAwareComponent(this); + } + + /** {@inheritDoc} */ + @Override public void stop0(boolean cancel) { + cancelConsistentCut(new IgniteCheckedException("Ignite node is stopping.")); + } + + /** + * Stops Consistent Cut in case of baseline topology changed. + */ + @Override public void onInitBeforeTopologyLock(GridDhtPartitionsExchangeFuture fut) { + if (fut.changedBaseline() || fut.isBaselineNodeFailed()) + cancelConsistentCut(new IgniteCheckedException("Ignite topology changed, can't finish Consistent Cut.")); + } + + /** + * Registers transaction before it is committed and removed from {@link IgniteTxManager#activeTransactions()}. + * + * @param tx Transaction. + */ + public void onCommit(IgniteInternalTx tx) { + ConsistentCut cut = consistentCut(); + + if (cut != null && cut.baseline()) + ((BaselineConsistentCut)cut).onCommit(tx.finishFuture()); + } + + /** + * Wraps a transaction message if Consistent Cut is running. + * + * @param txMsg Transaction message to wrap. + * @param txCutId Consistent Cut ID after which transaction committed, if specified. + */ + public static GridCacheMessage wrapMessage( + GridCacheSharedContext<?, ?> cctx, + GridCacheMessage txMsg, + @Nullable UUID txCutId + ) { + if (cctx.consistentCutMgr() == null) + return txMsg; + + ConsistentCut cut = cctx.consistentCutMgr().consistentCut(); + + if (cut != null) + return new ConsistentCutAwareMessage(txMsg, cut.id(), txCutId); + + return txMsg; + } + + /** + * Handles received Consistent Cut ID from remote node. It compares it with the latest ID that local node is aware of. + * Init local Consistent Cut procedure if received ID is a new one. + * + * @param id Consistent Cut ID. + */ + public void handleConsistentCutId(UUID id) { + ConsistentCut cut = consistentCutRef.get(); + + if (cut != null || Objects.equals(id, lastFinishedCutId)) + return; + + boolean clientNode = cctx.kernalContext().clientNode() Review Comment: This variable must be renamed to something more meaningful. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
