[GitHub] [iotdb] SilverNarcissus commented on a change in pull request #2920: Fix unseq compaction file selector conflicts with time partition bug

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

SilverNarcissus commented on a change in pull request #2920:
URL: https://github.com/apache/iotdb/pull/2920#discussion_r603851927



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File path: server/src/main/java/org/apache/iotdb/db/engine/compaction/no/NoCompactionTsFileManagement.java
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@@ -28,41 +28,53 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
+import java.util.Set;
 import java.util.TreeSet;
+import java.util.concurrent.ConcurrentSkipListMap;
+import java.util.concurrent.CopyOnWriteArrayList;
 
 public class NoCompactionTsFileManagement extends TsFileManagement {
 
   private static final Logger logger = LoggerFactory.getLogger(NoCompactionTsFileManagement.class);
   // includes sealed and unsealed sequence TsFiles
-  private TreeSet<TsFileResource> sequenceFileTreeSet =
-      new TreeSet<>(
-          (o1, o2) -> {
-            try {
-              int rangeCompare =
-                  Long.compare(
-                      Long.parseLong(o1.getTsFile().getParentFile().getName()),
-                      Long.parseLong(o2.getTsFile().getParentFile().getName()));
-              return rangeCompare == 0
-                  ? compareFileName(o1.getTsFile(), o2.getTsFile())
-                  : rangeCompare;
-            } catch (NumberFormatException e) {
-              return compareFileName(o1.getTsFile(), o2.getTsFile());
-            }
-          });
+  private final Map<Long, TreeSet<TsFileResource>> sequenceFileTreeSetMap =

Review comment:
       You use ConcurrentSkipListMap to improve the concurrency. But the value of this map is treeset, which is not thread safe. In your later code, you use synchronize in "add" method but never use synchronize in "contains method". That will cause a concurrency problem. As far as I'm concerned, I recommend to use synchronize on this complex structure. Use TreeMap and tree set and use synchronize at every read and write.




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