org.apache.flink.runtime.state.gemini.engine.vm.EvictPolicy Maven / Gradle / Ivy
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* distributed with this work for additional information
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* 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,
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*/
package org.apache.flink.runtime.state.gemini.engine.vm;
import org.apache.flink.runtime.state.gemini.engine.GRegion;
import org.apache.flink.runtime.state.gemini.engine.page.PageAddress;
import org.apache.flink.shaded.netty4.io.netty.util.concurrent.EventExecutor;
/**
* EvictPolicy.
*/
public interface EvictPolicy extends Runnable {
/**
* memory used water mark.
*/
enum MemoryUsedWaterMark {
Normal((short) 0), Low((short) 1), Middle((short) 2), High((short) 3);
short value;
MemoryUsedWaterMark(short value) {
this.value = value;
}
public short getShortValue() {
return value;
}
}
/**
* initialize EvictHandlerSepImpl according to RegionEventExecutor of GRegion.
*
* @param gRegion region instance.
*/
void addRegion(GRegion gRegion);
/**
* Return the EvictHandler for the given region.
*/
EvictHandlerSepImpl getEvictHandlerSepImpl(GRegion gRegion);
/**
* remove invalid page which is discarded because of compaction or splitting.
*
* @param gRegion gRegion instance.
* @param pageAddress The actual PageAddress, either PageAddressCompositeImpl or PageAddressSingleImpl.
* @return the total number of pages which were deleted.
*/
int removeInvalidPage(GRegion gRegion, PageAddress pageAddress);
/**
* add new page into Evict pool.
*
* @param gRegion gRegion instance.
* @param pageAddress The actual PageAddress, either PageAddressCompositeImpl or PageAddressSingleImpl.
*/
void addPage(GRegion gRegion, PageAddress pageAddress);
/**
* record memory used by page which will be added in the Cache. if neccessay will trigger evicting.
*
* @param gRegion gRegion instance
* @param regionEventExecutor gRegion executor instance
* @param logicPageSize size of page.
* @param needEvict whether do evict.
*/
void addPageUsedMemory(GRegion gRegion, EventExecutor regionEventExecutor, int logicPageSize, boolean needEvict);
/**
* to try to prepare flushing page.
*
* @param gRegion gRegion instance.
* @param minSize which size is needed soon.
*/
void tryPrepareFlush(GRegion gRegion, int minSize);
/**
* get MemoryUsedWaterMark of EvictHandler who handles this region when adding size of addSize.
* @param gRegion gRegion instance.
* @param addSize size.
* @return MemoryUsedWaterMark
*/
MemoryUsedWaterMark getMemoryUsedWaterMark(GRegion gRegion, int addSize);
/**
* shutdown.
*/
void shutdown();
}