org.apache.flink.runtime.state.ttl.TtlIncrementalCleanup Maven / Gradle / Ivy
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* 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.flink.runtime.state.ttl;
import org.apache.flink.runtime.state.StateEntry;
import org.apache.flink.runtime.state.internal.InternalKvState.StateIncrementalVisitor;
import org.apache.flink.util.FlinkRuntimeException;
import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;
import java.util.Collection;
/**
* Incremental cleanup of state with TTL.
*
* @param type of state key
* @param type of state namespace
*/
class TtlIncrementalCleanup {
/** Global state entry iterator is advanced for {@code cleanupSize} entries. */
@Nonnegative
private final int cleanupSize;
/** Particular state with TTL object is used to check whether currently iterated entry has expired. */
private AbstractTtlState ttlState;
/** Global state entry iterator, advanced for {@code cleanupSize} entries every state and/or record processing. */
private StateIncrementalVisitor stateIterator;
/**
* TtlIncrementalCleanup constructor.
*
* @param cleanupSize max number of queued keys to incrementally cleanup upon state access
*/
TtlIncrementalCleanup(@Nonnegative int cleanupSize) {
this.cleanupSize = cleanupSize;
}
void stateAccessed() {
initIteratorIfNot();
try {
runCleanup();
} catch (Throwable t) {
throw new FlinkRuntimeException("Failed to incrementally clean up state with TTL", t);
}
}
private void initIteratorIfNot() {
if (stateIterator == null || !stateIterator.hasNext()) {
stateIterator = ttlState.original.getStateIncrementalVisitor(cleanupSize);
}
}
private void runCleanup() {
int entryNum = 0;
Collection> nextEntries;
while (
entryNum < cleanupSize &&
stateIterator.hasNext() &&
!(nextEntries = stateIterator.nextEntries()).isEmpty()) {
for (StateEntry state : nextEntries) {
S cleanState = ttlState.getUnexpiredOrNull(state.getState());
if (cleanState == null) {
stateIterator.remove(state);
} else if (cleanState != state.getState()) {
stateIterator.update(state, cleanState);
}
}
entryNum += nextEntries.size();
}
}
/**
* As TTL state wrapper depends on this class through access callback,
* it has to be set here after its construction is done.
*/
public void setTtlState(@Nonnull AbstractTtlState ttlState) {
this.ttlState = ttlState;
}
int getCleanupSize() {
return cleanupSize;
}
}