akashrn5 commented on a change in pull request #3908:
URL: https://github.com/apache/carbondata/pull/3908#discussion_r486985758



##########
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:
       As you mentioned first time it will take lot of time, but query time we 
will get benefit. You said matched partitions and since here for every load we 
are trying to cache, we wont be able to get any matched partitions right?
   
   It is something similar to our Indexes(MV, SI) etc where we load all segment 
at once in first time and from next time we do incremental, as @QiangCai 
mentioned. So here from subsequent loads, only that segment should be 
considered, which i think its being taken care.
   
   @ajantha-bhat are you trying to say to change to handle in query or load 
itself? Correct me, if i'm wrong. 




----------------------------------------------------------------
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


Reply via email to