Abyss-lord commented on code in PR #7200: URL: https://github.com/apache/gravitino/pull/7200#discussion_r2106805727
########## core/src/main/java/org/apache/gravitino/cache/EntityCacheWeigher.java: ########## @@ -0,0 +1,123 @@ +/* + * 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.gravitino.cache; + +import com.github.benmanes.caffeine.cache.Weigher; +import java.util.List; +import lombok.NonNull; +import org.apache.gravitino.Entity; +import org.checkerframework.checker.index.qual.NonNegative; + +/** + * A {@link Weigher} implementation that calculates the weight of an entity based on its type. The + * weight is calculated as follows: + * + * <ul> + * <li>Metalake: 100 + * <li>Catalog: 75 + * <li>Schema: 50 + * <li>Other: 15 + * </ul> + */ +public class EntityCacheWeigher implements Weigher<EntityCacheKey, List<Entity>> { + private static final EntityCacheWeigher INSTANCE = new EntityCacheWeigher(); + + private EntityCacheWeigher() {} + + public static final int METALAKE_WEIGHT = 100; + public static final int CATALOG_WEIGHT = 75; + public static final int SCHEMA_WEIGHT = 50; + public static final int OTHER_WEIGHT = 15; + + /** + * Returns the maximum weight that can be stored in the cache. + * + * <p>The total weight is estimated based on the expected number of metadata entities: + * + * <ul> + * <li>~10 Metalakes per Gravitino instance + * <li>~200 Catalogs per Metalake + * <li>~1000 Schemas per Catalog + * </ul> + * + * <p>The total estimated entity count is: + * + * <pre> + * 10 * METALAKE_WEIGHT + * + (10 * 200) * CATALOG_WEIGHT + * + (10 * 200 * 1000) * SCHEMA_WEIGHT + * </pre> + * + * <p>To provide headroom and avoid early eviction, the result is multiplied by 2: + * + * <pre> + * total = 2 * (10 * METALAKE_WEIGHT + 2000 * CATALOG_WEIGHT + 2_000_000 * SCHEMA_WEIGHT) + * </pre> + * + * @return The maximum weight that can be stored in the cache. + */ + public static long getMaxWeight() { + return 2 + * (METALAKE_WEIGHT * 10 + CATALOG_WEIGHT * (10 * 200) + SCHEMA_WEIGHT * (10 * 200 * 1000)); + } + + /** + * Returns the singleton instance of the {@link EntityCacheWeigher}. + * + * @return the singleton instance of the {@link EntityCacheWeigher}. + */ + public static EntityCacheWeigher getInstance() { + return INSTANCE; + } + + /** {@inheritDoc} */ + @Override + public @NonNegative int weigh( + @NonNull EntityCacheKey storeEntityCacheKey, @NonNull List<Entity> entities) { + int weight = 0; + for (Entity entity : entities) { + weight += calculateWeight(entity.type()); + } + return weight; Review Comment: Regarding the behavior when a single entry's weight exceeds the configured maximumWeight: > Caffeine will not cache the entry if its weight alone exceeds the limit. It will silently skip the entry without throwing an exception or error. -- 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: commits-unsubscr...@gravitino.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
