[GitHub] [iotdb] yuqi1129 commented on a change in pull request #2353: [IOTDB-1083] There is no need to get write lock each time when we try…

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

yuqi1129 commented on a change in pull request #2353:
URL: https://github.com/apache/iotdb/pull/2353#discussion_r562316844



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File path: server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java
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@@ -969,87 +969,86 @@ private TsFileProcessor getOrCreateTsFileProcessorIntern(long timeRangeId,
       boolean sequence)
       throws IOException, DiskSpaceInsufficientException {
 
-    TsFileProcessor res;
-    // we have to ensure only one thread can change workSequenceTsFileProcessors
-    writeLock();
-    try {
-      res = tsFileProcessorTreeMap.get(timeRangeId);
-      if (res == null) {
-        // we have to remove oldest processor to control the num of the memtables
-        // TODO: use a method to control the number of memtables
-        if (tsFileProcessorTreeMap.size()
-            >= IoTDBDescriptor.getInstance().getConfig().getConcurrentWritingTimePartition()) {
-          Map.Entry<Long, TsFileProcessor> processorEntry = tsFileProcessorTreeMap.firstEntry();
-          logger.info(
-              "will close a {} TsFile because too many active partitions ({} > {}) in the storage group {},",
-              sequence, tsFileProcessorTreeMap.size(),
-              IoTDBDescriptor.getInstance().getConfig().getConcurrentWritingTimePartition(),
-              storageGroupName);
-          asyncCloseOneTsFileProcessor(sequence, processorEntry.getValue());
-        }
+    TsFileProcessor res = tsFileProcessorTreeMap.get(timeRangeId);
 
-        // build new processor
-        TsFileProcessor newProcessor = createTsFileProcessor(sequence, timeRangeId);
-        tsFileProcessorTreeMap.put(timeRangeId, newProcessor);
-        tsFileManagement.add(newProcessor.getTsFileResource(), sequence);
-        res = newProcessor;
-      }
+    //Use double-check to shorten the lock range
+    if (null == res) {
+      writeLock();

Review comment:
       Yes, further optimization about the lock can be made, i will remove related duplication code later, thanks




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