cadonna commented on code in PR #13756: URL: https://github.com/apache/kafka/pull/13756#discussion_r1226821666
########## streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBTimeOrderedKeyValueBuffer.java: ########## @@ -0,0 +1,171 @@ +/* + * 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.kafka.streams.state.internals; + +import org.apache.kafka.common.serialization.Serde; +import org.apache.kafka.common.utils.Bytes; +import org.apache.kafka.streams.KeyValue; +import org.apache.kafka.streams.processor.ProcessorContext; +import org.apache.kafka.streams.processor.StateStore; +import org.apache.kafka.streams.processor.StateStoreContext; +import org.apache.kafka.streams.processor.api.Record; +import org.apache.kafka.streams.processor.internals.ProcessorRecordContext; +import org.apache.kafka.streams.processor.internals.SerdeGetter; +import org.apache.kafka.streams.state.KeyValueIterator; +import org.apache.kafka.streams.state.ValueAndTimestamp; + +import java.nio.ByteBuffer; +import java.time.Duration; +import java.util.function.Consumer; +import java.util.function.Supplier; + +import static java.util.Objects.requireNonNull; + +public class RocksDBTimeOrderedKeyValueBuffer<K, V, T> extends WrappedStateStore<RocksDBTimeOrderedKeyValueSegmentedBytesStore, Object, Object> implements TimeOrderedKeyValueBuffer<K, V, V> { + + private final long gracePeriod; + private long bufferSize; + private long minTimestamp; + private int numRecords; + private Serde<K> keySerde; + private Serde<V> valueSerde; + private final String topic; + private int seqnum; + + public RocksDBTimeOrderedKeyValueBuffer(final RocksDBTimeOrderedKeyValueSegmentedBytesStore store, + final Duration gracePeriod, + final String topic) { + super(store); + this.gracePeriod = gracePeriod.toMillis(); + minTimestamp = Long.MAX_VALUE; + numRecords = 0; + bufferSize = 0; + seqnum = 0; + this.topic = topic; + } + + @SuppressWarnings("unchecked") + @Override + public void setSerdesIfNull(final SerdeGetter getter) { + keySerde = keySerde == null ? (Serde<K>) getter.keySerde() : keySerde; + valueSerde = valueSerde == null ? getter.valueSerde() : valueSerde; + } + + @Deprecated + @Override + public void init(final ProcessorContext context, final StateStore root) { + wrapped().init(context, wrapped()); + } + + @Override + public void init(final StateStoreContext context, final StateStore root) { + wrapped().init(context, wrapped()); + } + + @Override + public void evictWhile(final Supplier<Boolean> predicate, final Consumer<Eviction<K, V>> callback) { + KeyValue<Bytes, byte[]> keyValue; + + if (predicate.get()) { + try (final KeyValueIterator<Bytes, byte[]> iterator = wrapped() + .fetchAll(0, wrapped().observedStreamTime - gracePeriod)) { + while (iterator.hasNext() && predicate.get()) { + keyValue = iterator.next(); + + final BufferValue bufferValue = BufferValue.deserialize(ByteBuffer.wrap(keyValue.value)); + final K key = keySerde.deserializer().deserialize(topic, + PrefixedWindowKeySchemas.TimeFirstWindowKeySchema.extractStoreKeyBytes(keyValue.key.get())); + minTimestamp = bufferValue.context().timestamp(); + + if (wrapped().observedStreamTime - gracePeriod > minTimestamp) { + return; + } + + V value = valueSerde.deserializer().deserialize(topic, bufferValue.newValue()); + + if (bufferValue.context().timestamp() != minTimestamp) { + throw new IllegalStateException( + "minTimestamp [" + minTimestamp + "] did not match the actual min timestamp [" + + bufferValue.context().timestamp() + "]" + ); + } + + callback.accept(new Eviction<K, V>(key, value, bufferValue.context())); + + wrapped().remove(keyValue.key); + numRecords--; + bufferSize = bufferSize - computeRecordSize(keyValue.key, bufferValue); + } + if (numRecords == 0) { + minTimestamp = Long.MAX_VALUE; + } + } + } + } + + + @Override + public Maybe<ValueAndTimestamp<V>> priorValueForBuffered(final K key) { + return Maybe.undefined(); + } + + @Override + public void put(final long time, final Record<K, V> record, final ProcessorRecordContext recordContext) { + requireNonNull(record.value(), "value cannot be null"); + requireNonNull(recordContext, "recordContext cannot be null"); + if (wrapped().observedStreamTime - gracePeriod > record.timestamp()) { + return; + } + final Bytes serializedKey = Bytes.wrap( + PrefixedWindowKeySchemas.TimeFirstWindowKeySchema.toStoreKeyBinary(keySerde.serializer().serialize(topic, record.key()), + record.timestamp(), + seqnum++).get()); Review Comment: Just increasing a local sequence number does not seem to be enough. Let's assume the following scenario: 1. Add record A with key X and timestamp 1: Record A would get sequence number 0 2. A commit takes place 3. Add record B with key X and timestamp 1: Record B would get sequence number 1 4. A failure happens 5. Record B would be re-read: This time it is added with sequence number 0, overwriting record A. I think you need to get the highest sequence number from the records in the state store at start up. Or maybe you can find a better solution. ########## streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBTimeOrderedKeyValueBuffer.java: ########## @@ -0,0 +1,171 @@ +/* + * 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.kafka.streams.state.internals; + +import org.apache.kafka.common.serialization.Serde; +import org.apache.kafka.common.utils.Bytes; +import org.apache.kafka.streams.KeyValue; +import org.apache.kafka.streams.processor.ProcessorContext; +import org.apache.kafka.streams.processor.StateStore; +import org.apache.kafka.streams.processor.StateStoreContext; +import org.apache.kafka.streams.processor.api.Record; +import org.apache.kafka.streams.processor.internals.ProcessorRecordContext; +import org.apache.kafka.streams.processor.internals.SerdeGetter; +import org.apache.kafka.streams.state.KeyValueIterator; +import org.apache.kafka.streams.state.ValueAndTimestamp; + +import java.nio.ByteBuffer; +import java.time.Duration; +import java.util.function.Consumer; +import java.util.function.Supplier; + +import static java.util.Objects.requireNonNull; + +public class RocksDBTimeOrderedKeyValueBuffer<K, V, T> extends WrappedStateStore<RocksDBTimeOrderedKeyValueSegmentedBytesStore, Object, Object> implements TimeOrderedKeyValueBuffer<K, V, V> { Review Comment: How much work would it be to avoid using segmented state stores? Do we have a guarantee that we do not create/open multiple state stores for `RocksDBTimeOrderedKeyValueBuffer`? My main concern is that the code becomes really hard to read and understand if we use segemented state store where we do not actually need them. -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
