add properties

server/src/assembly/resources/conf/iotdb-engine.properties

@@ -183,6 +183,12 @@ memtable_size_threshold=1073741824
 
 avg_series_point_number_threshold=100000
 
+# When merge point number reaches this, merge the vmfile to the tsfile.
+merge_chunk_point_number=10000
+
+# When vmfiles merge times exceeds this, merge the vmfile to the tsfile.
+max_merge_chunk_num_in_tsfile=5
+
 # How many threads can concurrently flush. When <= 0, use CPU core number.
 concurrent_flush_thread=0
 

server/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java

@@ -248,6 +248,16 @@ public class IoTDBConfig {
    */
   private int avgSeriesPointNumberThreshold = 10000;
 
+  /**
+   * When merge point number reaches this, merge the vmfile to the tsfile.
+   */
+  private int mergeChunkPointNumberThreshold = 10000;
+
+  /**
+   * When vmfiles merge times exceeds this, merge the vmfile to the tsfile.
+   */
+  private int maxMergeChunkNumInTsFile = 5;
+
   /**
    * whether to cache meta data(ChunkMetaData and TsFileMetaData) or not.
    */
@@ -1231,6 +1241,21 @@ public class IoTDBConfig {
     this.avgSeriesPointNumberThreshold = avgSeriesPointNumberThreshold;
   }
 
+  public int getMergeChunkPointNumberThreshold() {
+    return mergeChunkPointNumberThreshold;
+  }
+
+  public void setMergeChunkPointNumberThreshold(int mergeChunkPointNumberThreshold) {
+    this.mergeChunkPointNumberThreshold = mergeChunkPointNumberThreshold;
+  }
+
+  public int getMaxMergeChunkNumInTsFile() {
+    return maxMergeChunkNumInTsFile;
+  }
+
+  public void setMaxMergeChunkNumInTsFile(int maxMergeChunkNumInTsFile) {
+    this.maxMergeChunkNumInTsFile = maxMergeChunkNumInTsFile;
+  }
   public MergeFileStrategy getMergeFileStrategy() {
     return mergeFileStrategy;
   }

server/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java

@@ -243,6 +243,14 @@ public class IoTDBDescriptor {
           .getProperty("avg_series_point_number_threshold",
               Integer.toString(conf.getAvgSeriesPointNumberThreshold()))));
 
+      conf.setMergeChunkPointNumberThreshold(Integer.parseInt(properties
+          .getProperty("merge_chunk_point_number",
+              Integer.toString(conf.getMergeChunkPointNumberThreshold()))));
+
+      conf.setMaxMergeChunkNumInTsFile(Integer.parseInt(properties
+          .getProperty("max_merge_chunk_num_in_tsfile",
+              Integer.toString(conf.getMaxMergeChunkNumInTsFile()))));
+
       conf.setEnableVm(Boolean.parseBoolean(properties
           .getProperty("enable_vm",
               Boolean.toString(conf.isEnableVm()))));

server/src/main/java/org/apache/iotdb/db/engine/storagegroup/TsFileProcessor.java

@@ -125,6 +125,7 @@ public class TsFileProcessor {
   private boolean sequence;
   private long totalMemTableSize;
 
+  private int mergeTimes = 0;
   private static final String FLUSH_QUERY_WRITE_LOCKED = "{}: {} get flushQueryLock write lock";
   private static final String FLUSH_QUERY_WRITE_RELEASE = "{}: {} get flushQueryLock write lock released";
 
@@ -698,9 +699,11 @@ public class TsFileProcessor {
             }
           }
           if ((vmPointNum + memTableToFlush.getTotalPointsNum()) / pathMeasurementSchemaMap.size()
-              > config.getAvgSeriesPointNumberThreshold()) {
+              > config.getMergeChunkPointNumberThreshold() 
+              || mergeTimes >= config.getMaxMergeChunkNumInTsFile()) {
             isVm = false;
             isFull = false;
+            mergeTimes = 0;
             flushTask = new MemTableFlushTask(memTableToFlush, writer, vmTsFileResources, vmWriters,
                 false, false,
                 sequence,
@@ -714,6 +717,7 @@ public class TsFileProcessor {
                   vmWriters, true, true,
                   sequence,
                   storageGroupName);
+              mergeTimes++;
             } else {
               isVm = true;
               isFull = false;