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Posted to commits@iotdb.apache.org by ja...@apache.org on 2021/05/27 11:14:07 UTC

[iotdb] 01/01: use google guava cache

This is an automated email from the ASF dual-hosted git repository.

jackietien pushed a commit to branch ChunkCacheBug
in repository https://gitbox.apache.org/repos/asf/iotdb.git

commit aadbf83a790457ddec7e0bfc4ef680c597e15253
Author: JackieTien97 <Ja...@foxmail.com>
AuthorDate: Thu May 27 19:12:34 2021 +0800

    use google guava cache
---
 server/pom.xml                                     |   6 +
 .../db/engine/cache/CacheHitRatioMonitor.java      |  16 +-
 .../engine/cache/CacheHitRatioMonitorMXBean.java   |   8 +-
 .../apache/iotdb/db/engine/cache/ChunkCache.java   | 154 +++++-----
 .../iotdb/db/engine/cache/LRULinkedHashMap.java    | 138 ---------
 .../db/engine/cache/TimeSeriesMetadataCache.java   | 319 ++++++++++-----------
 6 files changed, 228 insertions(+), 413 deletions(-)

diff --git a/server/pom.xml b/server/pom.xml
index 08944e2..0597e03 100644
--- a/server/pom.xml
+++ b/server/pom.xml
@@ -213,6 +213,12 @@
             <version>4.3.5</version>
             <scope>compile</scope>
         </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>29.0-jre</version>
+            <scope>compile</scope>
+        </dependency>
     </dependencies>
     <build>
         <plugins>
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitor.java b/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitor.java
index 51e9b1b..beda7fc 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitor.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitor.java
@@ -61,8 +61,8 @@ public class CacheHitRatioMonitor implements CacheHitRatioMonitorMXBean, IServic
   }
 
   @Override
-  public long getChunkCacheUsedMemory() {
-    return ChunkCache.getInstance().getUsedMemory();
+  public long getChunkEvictionCount() {
+    return ChunkCache.getInstance().getEvictionCount();
   }
 
   @Override
@@ -71,8 +71,8 @@ public class CacheHitRatioMonitor implements CacheHitRatioMonitorMXBean, IServic
   }
 
   @Override
-  public double getChunkCacheUsedMemoryProportion() {
-    return ChunkCache.getInstance().getUsedMemoryProportion();
+  public double getChunkCacheAverageLoadPenalty() {
+    return ChunkCache.getInstance().getAverageLoadPenalty();
   }
 
   @Override
@@ -86,8 +86,8 @@ public class CacheHitRatioMonitor implements CacheHitRatioMonitorMXBean, IServic
   }
 
   @Override
-  public long getTimeSeriesMetadataCacheUsedMemory() {
-    return TimeSeriesMetadataCache.getInstance().getUsedMemory();
+  public long getTimeSeriesMetadataCacheEvictionCount() {
+    return TimeSeriesMetadataCache.getInstance().getEvictionCount();
   }
 
   @Override
@@ -96,8 +96,8 @@ public class CacheHitRatioMonitor implements CacheHitRatioMonitorMXBean, IServic
   }
 
   @Override
-  public double getTimeSeriesCacheUsedMemoryProportion() {
-    return TimeSeriesMetadataCache.getInstance().getUsedMemoryProportion();
+  public double getTimeSeriesCacheAverageLoadPenalty() {
+    return TimeSeriesMetadataCache.getInstance().getAverageLoadPenalty();
   }
 
   @Override
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitorMXBean.java b/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitorMXBean.java
index 854fb1a..b1d48b7 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitorMXBean.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/cache/CacheHitRatioMonitorMXBean.java
@@ -22,21 +22,21 @@ public interface CacheHitRatioMonitorMXBean {
 
   double getChunkHitRatio();
 
-  long getChunkCacheUsedMemory();
+  long getChunkEvictionCount();
 
   long getChunkCacheMaxMemory();
 
-  double getChunkCacheUsedMemoryProportion();
+  double getChunkCacheAverageLoadPenalty();
 
   long getChunkCacheAverageSize();
 
   double getTimeSeriesMetadataHitRatio();
 
-  long getTimeSeriesMetadataCacheUsedMemory();
+  long getTimeSeriesMetadataCacheEvictionCount();
 
   long getTimeSeriesMetadataCacheMaxMemory();
 
-  double getTimeSeriesCacheUsedMemoryProportion();
+  double getTimeSeriesCacheAverageLoadPenalty();
 
   long getTimeSeriesMetaDataCacheAverageSize();
 
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/cache/ChunkCache.java b/server/src/main/java/org/apache/iotdb/db/engine/cache/ChunkCache.java
index 556075f..bb7b095 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/cache/ChunkCache.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/cache/ChunkCache.java
@@ -28,13 +28,16 @@ import org.apache.iotdb.tsfile.read.TsFileSequenceReader;
 import org.apache.iotdb.tsfile.read.common.Chunk;
 import org.apache.iotdb.tsfile.utils.RamUsageEstimator;
 
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import com.google.common.cache.Weigher;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.atomic.AtomicLong;
-import java.util.concurrent.locks.ReadWriteLock;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 /**
  * This class is used to cache <code>Chunk</code> of <code>ChunkMetaData</code> in IoTDB. The
@@ -49,39 +52,59 @@ public class ChunkCache {
       config.getAllocateMemoryForChunkCache();
   private static final boolean CACHE_ENABLE = config.isMetaDataCacheEnable();
 
-  private final LRULinkedHashMap<ChunkMetadata, Chunk> lruCache;
+  private final LoadingCache<ChunkMetadata, Chunk> lruCache;
 
-  private final AtomicLong cacheHitNum = new AtomicLong();
-  private final AtomicLong cacheRequestNum = new AtomicLong();
-
-  private final ReadWriteLock lock = new ReentrantReadWriteLock();
+  private final AtomicLong entryAverageSize = new AtomicLong(0);
 
   private ChunkCache() {
     if (CACHE_ENABLE) {
       logger.info("ChunkCache size = " + MEMORY_THRESHOLD_IN_CHUNK_CACHE);
     }
     lruCache =
-        new LRULinkedHashMap<ChunkMetadata, Chunk>(MEMORY_THRESHOLD_IN_CHUNK_CACHE) {
-
-          @Override
-          protected long calEntrySize(ChunkMetadata key, Chunk value) {
-            long currentSize;
-            if (count < 10) {
-              currentSize =
-                  RamUsageEstimator.NUM_BYTES_OBJECT_REF + RamUsageEstimator.sizeOf(value);
-              averageSize = ((averageSize * count) + currentSize) / (++count);
-            } else if (count < 100000) {
-              count++;
-              currentSize = averageSize;
-            } else {
-              averageSize =
-                  RamUsageEstimator.NUM_BYTES_OBJECT_REF + RamUsageEstimator.sizeOf(value);
-              count = 1;
-              currentSize = averageSize;
-            }
-            return currentSize;
-          }
-        };
+        CacheBuilder.newBuilder()
+            .maximumWeight(MEMORY_THRESHOLD_IN_CHUNK_CACHE)
+            .weigher(
+                new Weigher<ChunkMetadata, Chunk>() {
+
+                  int count = 0;
+                  int averageSize = 0;
+
+                  @Override
+                  public int weigh(ChunkMetadata chunkMetadata, Chunk chunk) {
+                    int currentSize;
+                    if (count < 10) {
+                      currentSize =
+                          (int)
+                              (RamUsageEstimator.NUM_BYTES_OBJECT_REF
+                                  + RamUsageEstimator.sizeOf(chunk));
+                      averageSize = ((averageSize * count) + currentSize) / (++count);
+                      entryAverageSize.set(averageSize);
+                    } else if (count < 100000) {
+                      count++;
+                      currentSize = averageSize;
+                    } else {
+                      averageSize =
+                          (int)
+                              (RamUsageEstimator.NUM_BYTES_OBJECT_REF
+                                  + RamUsageEstimator.sizeOf(chunk));
+                      count = 1;
+                      currentSize = averageSize;
+                      entryAverageSize.set(averageSize);
+                    }
+                    return currentSize;
+                  }
+                })
+            .recordStats()
+            .build(
+                new CacheLoader<ChunkMetadata, Chunk>() {
+                  @Override
+                  public Chunk load(ChunkMetadata chunkMetadata) throws Exception {
+                    TsFileSequenceReader reader =
+                        FileReaderManager.getInstance()
+                            .get(chunkMetadata.getFilePath(), chunkMetadata.isClosed());
+                    return reader.readMemChunk(chunkMetadata);
+                  }
+                });
   }
 
   public static ChunkCache getInstance() {
@@ -105,42 +128,18 @@ public class ChunkCache {
           chunkMetaData.getStatistics());
     }
 
-    cacheRequestNum.incrementAndGet();
-
     Chunk chunk;
-    lock.readLock().lock();
     try {
       chunk = lruCache.get(chunkMetaData);
-    } finally {
-      lock.readLock().unlock();
-    }
-    if (chunk != null) {
-      cacheHitNum.incrementAndGet();
-      printCacheLog(true);
-    } else {
-      printCacheLog(false);
-      TsFileSequenceReader reader =
-          FileReaderManager.getInstance()
-              .get(chunkMetaData.getFilePath(), chunkMetaData.isClosed());
-      try {
-        chunk = reader.readMemChunk(chunkMetaData);
-      } catch (IOException e) {
-        logger.error("something wrong happened while reading {}", reader.getFileName());
-        throw e;
-      }
-      lock.writeLock().lock();
-      try {
-        if (!lruCache.containsKey(chunkMetaData)) {
-          lruCache.put(chunkMetaData, chunk);
-        }
-      } finally {
-        lock.writeLock().unlock();
-      }
+    } catch (ExecutionException e) {
+      logger.error("something wrong happened while loading {}", chunkMetaData);
+      throw new IOException(e);
     }
 
     if (debug) {
       DEBUG_LOGGER.info("get chunk from cache whose meta data is: " + chunkMetaData);
     }
+
     return new Chunk(
         chunk.getHeader(),
         chunk.getData().duplicate(),
@@ -148,61 +147,38 @@ public class ChunkCache {
         chunkMetaData.getStatistics());
   }
 
-  private void printCacheLog(boolean isHit) {
-    if (!logger.isDebugEnabled()) {
-      return;
-    }
-    logger.debug(
-        "[ChunkMetaData cache {}hit] The number of requests for cache is {}, hit rate is {}.",
-        isHit ? "" : "didn't ",
-        cacheRequestNum.get(),
-        cacheHitNum.get() * 1.0 / cacheRequestNum.get());
-  }
-
   public double calculateChunkHitRatio() {
-    if (cacheRequestNum.get() != 0) {
-      return cacheHitNum.get() * 1.0 / cacheRequestNum.get();
-    } else {
-      return 0;
-    }
+    return lruCache.stats().hitRate();
   }
 
-  public long getUsedMemory() {
-    return lruCache.getUsedMemory();
+  public long getEvictionCount() {
+    return lruCache.stats().evictionCount();
   }
 
   public long getMaxMemory() {
-    return lruCache.getMaxMemory();
+    return MEMORY_THRESHOLD_IN_CHUNK_CACHE;
   }
 
-  public double getUsedMemoryProportion() {
-    return lruCache.getUsedMemoryProportion();
+  public double getAverageLoadPenalty() {
+    return lruCache.stats().averageLoadPenalty();
   }
 
   public long getAverageSize() {
-    return lruCache.getAverageSize();
+    return entryAverageSize.get();
   }
 
   /** clear LRUCache. */
   public void clear() {
-    lock.writeLock().lock();
-    if (lruCache != null) {
-      lruCache.clear();
-    }
-    lock.writeLock().unlock();
+    lruCache.cleanUp();
   }
 
   public void remove(ChunkMetadata chunkMetaData) {
-    lock.writeLock().lock();
-    if (chunkMetaData != null) {
-      lruCache.remove(chunkMetaData);
-    }
-    lock.writeLock().unlock();
+    lruCache.invalidate(chunkMetaData);
   }
 
   @TestOnly
   public boolean isEmpty() {
-    return lruCache.isEmpty();
+    return lruCache.size() == 0;
   }
 
   /** singleton pattern. */
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/cache/LRULinkedHashMap.java b/server/src/main/java/org/apache/iotdb/db/engine/cache/LRULinkedHashMap.java
deleted file mode 100644
index 6246574..0000000
--- a/server/src/main/java/org/apache/iotdb/db/engine/cache/LRULinkedHashMap.java
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
- * 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.iotdb.db.engine.cache;
-
-import org.apache.iotdb.tsfile.common.cache.Accountable;
-
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.Map.Entry;
-import java.util.Set;
-
-/** This class is an LRU cache. <b>Note: It's not thread safe.</b> */
-public abstract class LRULinkedHashMap<K extends Accountable, V> {
-
-  private static final float LOAD_FACTOR_MAP = 0.75f;
-  private static final int INITIAL_CAPACITY = 128;
-  private static final float RETAIN_PERCENT = 0.9f;
-  private static final int MAP_ENTRY_SIZE = 40;
-
-  private final LinkedHashMap<K, V> linkedHashMap;
-
-  /** maximum memory threshold. */
-  private final long maxMemory;
-  /** current used memory. */
-  private long usedMemory;
-
-  /** memory size we need to retain while the cache is full */
-  private final long retainMemory;
-
-  protected int count = 0;
-  protected long averageSize = 0;
-
-  public LRULinkedHashMap(long maxMemory) {
-    this.linkedHashMap = new LinkedHashMap<>(INITIAL_CAPACITY, LOAD_FACTOR_MAP, true);
-    this.maxMemory = maxMemory;
-    this.retainMemory = (long) (maxMemory * RETAIN_PERCENT);
-  }
-
-  public V put(K key, V value) {
-    long size = calEntrySize(key, value) + MAP_ENTRY_SIZE;
-    key.setRamSize(size);
-    usedMemory += size;
-    V v = linkedHashMap.put(key, value);
-    if (usedMemory > maxMemory) {
-      Iterator<Entry<K, V>> iterator = linkedHashMap.entrySet().iterator();
-      while (usedMemory > retainMemory && iterator.hasNext()) {
-        Entry<K, V> entry = iterator.next();
-        usedMemory -= entry.getKey().getRamSize();
-        iterator.remove();
-      }
-    }
-    return v;
-  }
-
-  public V get(K key) {
-    return linkedHashMap.get(key);
-  }
-
-  public boolean containsKey(K key) {
-    return linkedHashMap.containsKey(key);
-  }
-
-  public void clear() {
-    linkedHashMap.clear();
-    usedMemory = 0;
-    count = 0;
-    averageSize = 0;
-  }
-
-  public V remove(K key) {
-    V v = linkedHashMap.remove(key);
-    if (v != null && key != null) {
-      usedMemory -= key.getRamSize();
-    }
-    return v;
-  }
-
-  /** approximately estimate the additional size of key and value. */
-  protected abstract long calEntrySize(K key, V value);
-
-  /** calculate the proportion of used memory. */
-  public double getUsedMemoryProportion() {
-    return usedMemory * 1.0 / maxMemory;
-  }
-
-  public long getUsedMemory() {
-    return usedMemory;
-  }
-
-  public long getMaxMemory() {
-    return maxMemory;
-  }
-
-  public long getAverageSize() {
-    return averageSize;
-  }
-
-  public Set<Entry<K, V>> entrySet() {
-    return linkedHashMap.entrySet();
-  }
-
-  public boolean isEmpty() {
-    return linkedHashMap.isEmpty();
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-    return super.equals(o);
-  }
-
-  @Override
-  public int hashCode() {
-    return super.hashCode();
-  }
-}
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/cache/TimeSeriesMetadataCache.java b/server/src/main/java/org/apache/iotdb/db/engine/cache/TimeSeriesMetadataCache.java
index 17d3f32..f5ff011 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/cache/TimeSeriesMetadataCache.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/cache/TimeSeriesMetadataCache.java
@@ -24,7 +24,6 @@ import org.apache.iotdb.db.conf.IoTDBConstant;
 import org.apache.iotdb.db.conf.IoTDBDescriptor;
 import org.apache.iotdb.db.query.control.FileReaderManager;
 import org.apache.iotdb.db.utils.TestOnly;
-import org.apache.iotdb.tsfile.common.cache.Accountable;
 import org.apache.iotdb.tsfile.file.metadata.ChunkMetadata;
 import org.apache.iotdb.tsfile.file.metadata.TimeseriesMetadata;
 import org.apache.iotdb.tsfile.read.TsFileSequenceReader;
@@ -32,6 +31,10 @@ import org.apache.iotdb.tsfile.read.common.Path;
 import org.apache.iotdb.tsfile.utils.BloomFilter;
 import org.apache.iotdb.tsfile.utils.RamUsageEstimator;
 
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import com.google.common.cache.Weigher;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -39,14 +42,13 @@ import java.io.IOException;
 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
 import java.util.WeakHashMap;
 import java.util.concurrent.atomic.AtomicLong;
-import java.util.concurrent.locks.ReadWriteLock;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 /**
  * This class is used to cache <code>TimeSeriesMetadata</code> in IoTDB. The caching strategy is
@@ -61,12 +63,9 @@ public class TimeSeriesMetadataCache {
       config.getAllocateMemoryForTimeSeriesMetaDataCache();
   private static final boolean CACHE_ENABLE = config.isMetaDataCacheEnable();
 
-  private final LRULinkedHashMap<TimeSeriesMetadataCacheKey, TimeseriesMetadata> lruCache;
+  private final LoadingCache<TimeSeriesMetadataCacheKey, TimeseriesMetadata> lruCache;
 
-  private final AtomicLong cacheHitNum = new AtomicLong();
-  private final AtomicLong cacheRequestNum = new AtomicLong();
-
-  private final ReadWriteLock lock = new ReentrantReadWriteLock();
+  private final AtomicLong entryAverageSize = new AtomicLong(0);
 
   private final Map<String, WeakReference<String>> devices =
       Collections.synchronizedMap(new WeakHashMap<>());
@@ -78,46 +77,75 @@ public class TimeSeriesMetadataCache {
           "TimeseriesMetadataCache size = " + MEMORY_THRESHOLD_IN_TIME_SERIES_METADATA_CACHE);
     }
     lruCache =
-        new LRULinkedHashMap<TimeSeriesMetadataCacheKey, TimeseriesMetadata>(
-            MEMORY_THRESHOLD_IN_TIME_SERIES_METADATA_CACHE) {
-
-          @Override
-          protected long calEntrySize(TimeSeriesMetadataCacheKey key, TimeseriesMetadata value) {
-            long currentSize;
-            if (count < 10) {
-              currentSize =
-                  RamUsageEstimator.shallowSizeOf(key)
-                      + RamUsageEstimator.sizeOf(key.device)
-                      + RamUsageEstimator.sizeOf(key.measurement)
-                      + RamUsageEstimator.shallowSizeOf(value)
-                      + RamUsageEstimator.sizeOf(value.getMeasurementId())
-                      + RamUsageEstimator.shallowSizeOf(value.getStatistics())
-                      + (((ChunkMetadata) value.getChunkMetadataList().get(0)).calculateRamSize()
-                              + RamUsageEstimator.NUM_BYTES_OBJECT_REF)
-                          * value.getChunkMetadataList().size()
-                      + RamUsageEstimator.shallowSizeOf(value.getChunkMetadataList());
-              averageSize = ((averageSize * count) + currentSize) / (++count);
-            } else if (count < 100000) {
-              count++;
-              currentSize = averageSize;
-            } else {
-              averageSize =
-                  RamUsageEstimator.shallowSizeOf(key)
-                      + RamUsageEstimator.sizeOf(key.device)
-                      + RamUsageEstimator.sizeOf(key.measurement)
-                      + RamUsageEstimator.shallowSizeOf(value)
-                      + RamUsageEstimator.sizeOf(value.getMeasurementId())
-                      + RamUsageEstimator.shallowSizeOf(value.getStatistics())
-                      + (((ChunkMetadata) value.getChunkMetadataList().get(0)).calculateRamSize()
-                              + RamUsageEstimator.NUM_BYTES_OBJECT_REF)
-                          * value.getChunkMetadataList().size()
-                      + RamUsageEstimator.shallowSizeOf(value.getChunkMetadataList());
-              count = 1;
-              currentSize = averageSize;
-            }
-            return currentSize;
-          }
-        };
+        CacheBuilder.newBuilder()
+            .maximumWeight(MEMORY_THRESHOLD_IN_TIME_SERIES_METADATA_CACHE)
+            .weigher(
+                new Weigher<TimeSeriesMetadataCacheKey, TimeseriesMetadata>() {
+
+                  int count = 0;
+                  int averageSize = 0;
+
+                  @Override
+                  public int weigh(TimeSeriesMetadataCacheKey key, TimeseriesMetadata value) {
+                    int currentSize;
+                    if (count < 10) {
+                      currentSize =
+                          (int)
+                              (RamUsageEstimator.shallowSizeOf(key)
+                                  + RamUsageEstimator.sizeOf(key.device)
+                                  + RamUsageEstimator.sizeOf(key.measurement)
+                                  + RamUsageEstimator.shallowSizeOf(value)
+                                  + RamUsageEstimator.sizeOf(value.getMeasurementId())
+                                  + RamUsageEstimator.shallowSizeOf(value.getStatistics())
+                                  + (((ChunkMetadata) value.getChunkMetadataList().get(0))
+                                              .calculateRamSize()
+                                          + RamUsageEstimator.NUM_BYTES_OBJECT_REF)
+                                      * value.getChunkMetadataList().size()
+                                  + RamUsageEstimator.shallowSizeOf(value.getChunkMetadataList()));
+                      averageSize = ((averageSize * count) + currentSize) / (++count);
+                      entryAverageSize.set(averageSize);
+                    } else if (count < 100000) {
+                      count++;
+                      currentSize = averageSize;
+                    } else {
+                      averageSize =
+                          (int)
+                              (RamUsageEstimator.shallowSizeOf(key)
+                                  + RamUsageEstimator.sizeOf(key.device)
+                                  + RamUsageEstimator.sizeOf(key.measurement)
+                                  + RamUsageEstimator.shallowSizeOf(value)
+                                  + RamUsageEstimator.sizeOf(value.getMeasurementId())
+                                  + RamUsageEstimator.shallowSizeOf(value.getStatistics())
+                                  + (((ChunkMetadata) value.getChunkMetadataList().get(0))
+                                              .calculateRamSize()
+                                          + RamUsageEstimator.NUM_BYTES_OBJECT_REF)
+                                      * value.getChunkMetadataList().size()
+                                  + RamUsageEstimator.shallowSizeOf(value.getChunkMetadataList()));
+                      count = 1;
+                      currentSize = averageSize;
+                      entryAverageSize.set(averageSize);
+                    }
+                    return currentSize;
+                  }
+                })
+            .recordStats()
+            .build(
+                new CacheLoader<TimeSeriesMetadataCacheKey, TimeseriesMetadata>() {
+                  @Override
+                  public TimeseriesMetadata load(TimeSeriesMetadataCacheKey key) throws Exception {
+                    // bloom filter part
+                    TsFileSequenceReader reader =
+                        FileReaderManager.getInstance().get(key.filePath, true);
+                    BloomFilter bloomFilter = reader.readBloomFilter();
+                    if (bloomFilter != null
+                        && !bloomFilter.contains(
+                            key.device + IoTDBConstant.PATH_SEPARATOR + key.measurement)) {
+                      return null;
+                    }
+                    return reader.readTimeseriesMetadata(
+                        new Path(key.device, key.measurement), false);
+                  }
+                });
   }
 
   public static TimeSeriesMetadataCache getInstance() {
@@ -143,20 +171,9 @@ public class TimeSeriesMetadataCache {
       return reader.readTimeseriesMetadata(new Path(key.device, key.measurement), false);
     }
 
-    cacheRequestNum.incrementAndGet();
+    TimeseriesMetadata timeseriesMetadata = lruCache.getIfPresent(key);
 
-    TimeseriesMetadata timeseriesMetadata;
-    lock.readLock().lock();
-    try {
-      timeseriesMetadata = lruCache.get(key);
-    } finally {
-      lock.readLock().unlock();
-    }
-
-    if (timeseriesMetadata != null) {
-      cacheHitNum.incrementAndGet();
-      printCacheLog(true);
-    } else {
+    if (timeseriesMetadata == null) {
       if (debug) {
         DEBUG_LOGGER.info(
             "Cache miss: {}.{} in file: {}", key.device, key.measurement, key.filePath);
@@ -166,16 +183,8 @@ public class TimeSeriesMetadataCache {
       synchronized (
           devices.computeIfAbsent(key.device + SEPARATOR + key.filePath, WeakReference::new)) {
         // double check
-        lock.readLock().lock();
-        try {
-          timeseriesMetadata = lruCache.get(key);
-        } finally {
-          lock.readLock().unlock();
-        }
-        if (timeseriesMetadata != null) {
-          cacheHitNum.incrementAndGet();
-          printCacheLog(true);
-        } else {
+        timeseriesMetadata = lruCache.getIfPresent(key);
+        if (timeseriesMetadata == null) {
           Path path = new Path(key.device, key.measurement);
           // bloom filter part
           TsFileSequenceReader reader = FileReaderManager.getInstance().get(key.filePath, true);
@@ -186,25 +195,17 @@ public class TimeSeriesMetadataCache {
             }
             return null;
           }
-          printCacheLog(false);
           List<TimeseriesMetadata> timeSeriesMetadataList =
               reader.readTimeseriesMetadata(path, allSensors);
           // put TimeSeriesMetadata of all sensors used in this query into cache
-          lock.writeLock().lock();
-          try {
-            timeSeriesMetadataList.forEach(
-                metadata -> {
-                  TimeSeriesMetadataCacheKey k =
-                      new TimeSeriesMetadataCacheKey(
-                          key.filePath, key.device, metadata.getMeasurementId());
-                  if (!lruCache.containsKey(k)) {
-                    lruCache.put(k, metadata);
-                  }
-                });
-            timeseriesMetadata = lruCache.get(key);
-          } finally {
-            lock.writeLock().unlock();
-          }
+          timeSeriesMetadataList.forEach(
+              metadata -> {
+                TimeSeriesMetadataCacheKey k =
+                    new TimeSeriesMetadataCacheKey(
+                        key.filePath, key.device, metadata.getMeasurementId());
+                lruCache.put(k, metadata);
+              });
+          timeseriesMetadata = lruCache.getIfPresent(key);
         }
       }
     }
@@ -246,16 +247,11 @@ public class TimeSeriesMetadataCache {
       return reader.readTimeseriesMetadata(new Path(key.device, key.measurement), subSensorList);
     }
 
-    cacheRequestNum.incrementAndGet();
-
     List<TimeseriesMetadata> res = new ArrayList<>();
 
     getVectorTimeSeriesMetadataListFromCache(key, subSensorList, res);
 
-    if (!res.isEmpty()) {
-      cacheHitNum.incrementAndGet();
-      printCacheLog(true);
-    } else {
+    if (res.isEmpty()) {
       if (debug) {
         DEBUG_LOGGER.info(
             "Cache miss: {}.{} in file: {}", key.device, key.measurement, key.filePath);
@@ -266,10 +262,7 @@ public class TimeSeriesMetadataCache {
           devices.computeIfAbsent(key.device + SEPARATOR + key.filePath, WeakReference::new)) {
         // double check
         getVectorTimeSeriesMetadataListFromCache(key, subSensorList, res);
-        if (!res.isEmpty()) {
-          cacheHitNum.incrementAndGet();
-          printCacheLog(true);
-        } else {
+        if (res.isEmpty()) {
           Path path = new Path(key.device, key.measurement);
           // bloom filter part
           TsFileSequenceReader reader = FileReaderManager.getInstance().get(key.filePath, true);
@@ -280,25 +273,21 @@ public class TimeSeriesMetadataCache {
             }
             return Collections.emptyList();
           }
-          printCacheLog(false);
           List<TimeseriesMetadata> timeSeriesMetadataList =
               reader.readTimeseriesMetadata(path, allSensors);
+          Map<TimeSeriesMetadataCacheKey, TimeseriesMetadata> map = new HashMap<>();
           // put TimeSeriesMetadata of all sensors used in this query into cache
-          lock.writeLock().lock();
-          try {
-            timeSeriesMetadataList.forEach(
-                metadata -> {
-                  TimeSeriesMetadataCacheKey k =
-                      new TimeSeriesMetadataCacheKey(
-                          key.filePath, key.device, metadata.getMeasurementId());
-                  if (!lruCache.containsKey(k)) {
-                    lruCache.put(k, metadata);
-                  }
-                });
-            getVectorTimeSeriesMetadataListFromCache(key, subSensorList, res);
-          } finally {
-            lock.writeLock().unlock();
-          }
+          timeSeriesMetadataList.forEach(
+              metadata -> {
+                TimeSeriesMetadataCacheKey k =
+                    new TimeSeriesMetadataCacheKey(
+                        key.filePath, key.device, metadata.getMeasurementId());
+                lruCache.put(k, metadata);
+                map.put(k, metadata);
+              });
+          // The reason we don't get from cache is in case that
+          // the cache capacity is too small to contains all the sub sensors of this vector
+          getVectorTimeSeriesMetadataListFromMap(key, subSensorList, res, map);
         }
       }
     }
@@ -323,94 +312,86 @@ public class TimeSeriesMetadataCache {
     }
   }
 
-  private void getVectorTimeSeriesMetadataListFromCache(
-      TimeSeriesMetadataCacheKey key, List<String> subSensorList, List<TimeseriesMetadata> res) {
-    lock.readLock().lock();
-    try {
-      TimeseriesMetadata timeseriesMetadata = lruCache.get(key);
-      if (timeseriesMetadata != null) {
-        res.add(timeseriesMetadata);
-        for (String subSensor : subSensorList) {
-          timeseriesMetadata =
-              lruCache.get(new TimeSeriesMetadataCacheKey(key.filePath, key.device, subSensor));
-          if (timeseriesMetadata != null) {
-            res.add(timeseriesMetadata);
-          } else {
-            res.clear();
-            break;
-          }
+  private void getVectorTimeSeriesMetadataListFromMap(
+      TimeSeriesMetadataCacheKey key,
+      List<String> subSensorList,
+      List<TimeseriesMetadata> res,
+      Map<TimeSeriesMetadataCacheKey, TimeseriesMetadata> map) {
+    TimeseriesMetadata timeseriesMetadata = map.get(key);
+    if (timeseriesMetadata != null) {
+      res.add(timeseriesMetadata);
+      for (String subSensor : subSensorList) {
+        timeseriesMetadata =
+            map.get(new TimeSeriesMetadataCacheKey(key.filePath, key.device, subSensor));
+        if (timeseriesMetadata != null) {
+          res.add(timeseriesMetadata);
+        } else {
+          res.clear();
+          break;
         }
       }
-    } finally {
-      lock.readLock().unlock();
     }
   }
 
-  private void printCacheLog(boolean isHit) {
-    if (!logger.isDebugEnabled()) {
-      return;
+  private void getVectorTimeSeriesMetadataListFromCache(
+      TimeSeriesMetadataCacheKey key, List<String> subSensorList, List<TimeseriesMetadata> res) {
+    TimeseriesMetadata timeseriesMetadata = lruCache.getIfPresent(key);
+    if (timeseriesMetadata != null) {
+      res.add(timeseriesMetadata);
+      for (String subSensor : subSensorList) {
+        timeseriesMetadata =
+            lruCache.getIfPresent(
+                new TimeSeriesMetadataCacheKey(key.filePath, key.device, subSensor));
+        if (timeseriesMetadata != null) {
+          res.add(timeseriesMetadata);
+        } else {
+          res.clear();
+          break;
+        }
+      }
     }
-    logger.debug(
-        "[TimeSeriesMetadata cache {}hit] The number of requests for cache is {}, hit rate is {}.",
-        isHit ? "" : "didn't ",
-        cacheRequestNum.get(),
-        cacheHitNum.get() * 1.0 / cacheRequestNum.get());
   }
 
   public double calculateTimeSeriesMetadataHitRatio() {
-    if (cacheRequestNum.get() != 0) {
-      return cacheHitNum.get() * 1.0 / cacheRequestNum.get();
-    } else {
-      return 0;
-    }
+    return lruCache.stats().hitRate();
   }
 
-  public long getUsedMemory() {
-    return lruCache.getUsedMemory();
+  public long getEvictionCount() {
+    return lruCache.stats().evictionCount();
   }
 
   public long getMaxMemory() {
-    return lruCache.getMaxMemory();
+    return MEMORY_THRESHOLD_IN_TIME_SERIES_METADATA_CACHE;
   }
 
-  public double getUsedMemoryProportion() {
-    return lruCache.getUsedMemoryProportion();
+  public double getAverageLoadPenalty() {
+    return lruCache.stats().averageLoadPenalty();
   }
 
   public long getAverageSize() {
-    return lruCache.getAverageSize();
+    return entryAverageSize.get();
   }
 
   /** clear LRUCache. */
   public void clear() {
-    lock.writeLock().lock();
-    if (lruCache != null) {
-      lruCache.clear();
-    }
-    lock.writeLock().unlock();
+    lruCache.cleanUp();
   }
 
   public void remove(TimeSeriesMetadataCacheKey key) {
-    lock.writeLock().lock();
-    if (key != null) {
-      lruCache.remove(key);
-    }
-    lock.writeLock().unlock();
+    lruCache.invalidate(key);
   }
 
   @TestOnly
   public boolean isEmpty() {
-    return lruCache.isEmpty();
+    return lruCache.size() == 0;
   }
 
-  public static class TimeSeriesMetadataCacheKey implements Accountable {
+  public static class TimeSeriesMetadataCacheKey {
 
     private final String filePath;
     private final String device;
     private final String measurement;
 
-    private long ramSize;
-
     public TimeSeriesMetadataCacheKey(String filePath, String device, String measurement) {
       this.filePath = filePath;
       this.device = device;
@@ -435,16 +416,6 @@ public class TimeSeriesMetadataCache {
     public int hashCode() {
       return Objects.hash(filePath, device, measurement);
     }
-
-    @Override
-    public void setRamSize(long size) {
-      this.ramSize = size;
-    }
-
-    @Override
-    public long getRamSize() {
-      return ramSize;
-    }
   }
 
   /** singleton pattern. */