[GitHub] [hive] szlta commented on a change in pull request #1961: HIVE-24726: Track required data for cache hydration

[GitBox <gi...@apache.org>]

szlta commented on a change in pull request #1961:
URL: https://github.com/apache/hive/pull/1961#discussion_r573618773



##########
File path: llap-server/src/java/org/apache/hadoop/hive/llap/cache/MemoryLimitedPathCache.java
##########
@@ -0,0 +1,60 @@
+/*
+ * Licensed 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.hadoop.hive.llap.cache;
+
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.Weigher;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hive.conf.HiveConf;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Memory limited version of the path cache.
+ */
+public class MemoryLimitedPathCache implements PathCache {
+
+  private static final Logger LOG = LoggerFactory.getLogger(MemoryLimitedPathCache.class);
+  private Cache<Object, String> internalCache;
+
+  public MemoryLimitedPathCache(Configuration conf) {
+    internalCache = CacheBuilder.newBuilder()
+        .maximumWeight(HiveConf.getSizeVar(conf, HiveConf.ConfVars.LLAP_IO_PATH_CACHE_SIZE))
+        .weigher(new PathWeigher())
+        .build();
+  }
+
+  @Override
+  public void touch(Object key, String val) {
+    if (key != null) {
+      internalCache.put(key, val);
+    }
+  }
+
+  @Override
+  public String resolve(Object key) {
+    return key != null ? internalCache.getIfPresent(key) : null;
+  }
+
+  private static class PathWeigher implements Weigher<Object, String> {
+
+    @Override
+    public int weigh(Object key, String value) {
+      // String memory footprint

Review comment:
       Please add more comments on why this is calculated like this.

##########
File path: llap-server/src/java/org/apache/hadoop/hive/llap/io/api/impl/LlapIoImpl.java
##########
@@ -112,6 +115,8 @@
   private final BufferUsageManager bufferManager;
   private final Configuration daemonConf;
   private final LowLevelCacheMemoryManager memoryManager;
+  private LowLevelCachePolicy realCachePolicy;

Review comment:
       Why was this refactor necessary? (similarly why for tracePool)




----------------------------------------------------------------
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:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: gitbox-unsubscribe@hive.apache.org
For additional commands, e-mail: gitbox-help@hive.apache.org