ascherbakoff commented on code in PR #7799: URL: https://github.com/apache/ignite-3/pull/7799#discussion_r3062336637
########## modules/table/src/main/java/org/apache/ignite/internal/table/distributed/replicator/PartitionInflights.java: ########## @@ -0,0 +1,161 @@ +/* + * 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.table.distributed.replicator; + +import static java.util.concurrent.atomic.AtomicLongFieldUpdater.newUpdater; +import static org.apache.ignite.internal.util.CompletableFutures.nullCompletedFuture; + +import java.util.UUID; +import java.util.concurrent.CompletableFuture; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.atomic.AtomicLongFieldUpdater; +import java.util.function.Predicate; +import org.apache.ignite.internal.partition.replicator.network.replication.RequestType; +import org.jetbrains.annotations.Nullable; +import org.jetbrains.annotations.TestOnly; + +/** + * Client transaction inflights tracker. + */ +public class PartitionInflights { + /** Hint for maximum concurrent txns. */ + private static final int MAX_CONCURRENT_TXNS_HINT = 1024; + + /** Field updater for inflights. */ + private static final AtomicLongFieldUpdater<CleanupContext> UPDATER = newUpdater(CleanupContext.class, "inflights"); + + /** Txn contexts. */ + private final ConcurrentHashMap<UUID, CleanupContext> txCtxMap = new ConcurrentHashMap<>(MAX_CONCURRENT_TXNS_HINT); + + /** + * Registers the inflight for a transaction. + * + * @param txId The transaction id. + * @param testPred Test predicate. + * @param requestType Request type. + * + * @return Cleanup context. + */ + @Nullable CleanupContext addInflight(UUID txId, Predicate<UUID> testPred, RequestType requestType) { + boolean[] res = {true}; + + CleanupContext ctx0 = txCtxMap.compute(txId, (uuid, ctx) -> { + if (ctx == null) { + ctx = new CleanupContext(); + } + + if (ctx.finishFut != null || testPred.test(txId)) { + res[0] = false; + } else { + UPDATER.incrementAndGet(ctx); + if (requestType.isWrite()) { + ctx.hasWrites = true; + } + } + + return ctx; + }); + + return res[0] ? ctx0 : null; + } + + /** + * Runs a closure under a transaction lock. + * + * @param txId Transaction id. + * @param r Runnable. + */ + public void runClosure(UUID txId, Runnable r) { + txCtxMap.compute(txId, (uuid, ctx) -> { + r.run(); + + return ctx; + }); + } + + /** + * Unregisters the inflight for a transaction. + * + * @param ctx Cleanup context. + */ + static void removeInflight(CleanupContext ctx) { + long val = UPDATER.decrementAndGet(ctx); + + if (ctx.finishFut != null && val == 0) { + ctx.finishFut.complete(null); + } + } + + /** + * Get finish future. + * + * @param txId Transaction id. + * @return The future. + */ + public @Nullable CleanupContext finishFuture(UUID txId) { + return txCtxMap.compute(txId, (uuid, ctx) -> { + if (ctx == null) { + return null; + } + + if (ctx.finishFut == null) { + ctx.finishFut = UPDATER.get(ctx) == 0 ? nullCompletedFuture() : new CompletableFuture<>(); + } + + // Avoiding a data race with a concurrent decrementing thread, which might not see finishFut publication. + if (UPDATER.get(ctx) == 0 && !ctx.finishFut.isDone()) { + ctx.finishFut = nullCompletedFuture(); + } Review Comment: I believe this code is correct. Double check after publication ensures finish future is completed, if it was not completed by decrementing thread. -- 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]
