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h2/src/main/org/h2/store/PageStore.java

@@ -175,6 +175,7 @@ public class PageStore implements CacheWriter {
     private boolean isNew;
     private long maxLogSize = Constants.DEFAULT_MAX_LOG_SIZE;
     private Session systemSession;
+    /** each free page is marked with a set bit */
     private BitField freed = new BitField();
     private ArrayList<PageFreeList> freeLists = New.arrayList();