ajantha-bhat commented on a change in pull request #3908: URL: https://github.com/apache/carbondata/pull/3908#discussion_r487008223
########## File path: integration/spark/src/main/scala/org/apache/spark/util/PartitionCacheManager.scala ########## @@ -0,0 +1,181 @@ +/* + * 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.spark.util + +import java.net.URI +import java.util + +import scala.collection.JavaConverters._ +import scala.collection.mutable + +import org.apache.log4j.Logger +import org.apache.spark.sql.catalyst.catalog.{CatalogStorageFormat, CatalogTablePartition} + +import org.apache.carbondata.common.logging.LogServiceFactory +import org.apache.carbondata.core.cache.{Cache, Cacheable, CarbonLRUCache} +import org.apache.carbondata.core.constants.CarbonCommonConstants +import org.apache.carbondata.core.datastore.impl.FileFactory +import org.apache.carbondata.core.index.Segment +import org.apache.carbondata.core.metadata.{AbsoluteTableIdentifier, SegmentFileStore} +import org.apache.carbondata.core.statusmanager.{LoadMetadataDetails, SegmentStatusManager} +import org.apache.carbondata.core.util.path.CarbonTablePath + +object PartitionCacheManager extends Cache[PartitionCacheKey, + java.util.List[CatalogTablePartition]] { + + private val CACHE = new CarbonLRUCache( + CarbonCommonConstants.CARBON_PARTITION_MAX_DRIVER_LRU_CACHE_SIZE, + CarbonCommonConstants.CARBON_MAX_LRU_CACHE_SIZE_DEFAULT) + + val LOGGER: Logger = LogServiceFactory.getLogService(this.getClass.getName) + + def get(identifier: PartitionCacheKey): java.util.List[CatalogTablePartition] = { + LOGGER.info("Reading partition values from store") + // read the tableStatus file to get valid and invalid segments + val validInvalidSegments = new SegmentStatusManager(AbsoluteTableIdentifier.from( + identifier.tablePath, null, null, identifier.tableId)) + .getValidAndInvalidSegments + val cacheablePartitionSpecs = validInvalidSegments.getValidSegments.asScala.map { segment => + val segmentFileName = segment.getSegmentFileName + val segmentFilePath = FileFactory.getCarbonFile( + CarbonTablePath.getSegmentFilePath(identifier.tablePath, segmentFileName)) + // read the last modified time + val segmentFileModifiedTime = segmentFilePath.getLastModifiedTime + val existingCache = CACHE.get(identifier.tableId) + if (existingCache != null) { + val segmentCache = CACHE.get(identifier.tableId).asInstanceOf[CacheablePartitionSpec] + .partitionSpecs.get(segment.getSegmentNo) + segmentCache match { + case Some(c) => + // check if cache needs to be updated + if (segmentFileModifiedTime > c._2) { + (segment.getSegmentNo, (readPartition(identifier, + segmentFilePath.getAbsolutePath), segmentFileModifiedTime)) + } else { + (segment.getSegmentNo, c) + } + case None => + (segment.getSegmentNo, (readPartition(identifier, + segmentFilePath.getAbsolutePath), segmentFileModifiedTime)) + } + } else { + // read the partitions if not available in cache. + (segment.getSegmentNo, (readPartition(identifier, Review comment: we have users with 200k segments. But the data is partitioned by date and time. so all queries will have partition columns filter. so they query-specific segments every time (without any degrade in query time) ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
