Moved docsWithFieldOffset, docsWithFieldLength, jumpTableEntryCount, denseRankPower metadata properties in the format to be after values metadata.

Author: martijnvg

server/src/main/java/org/elasticsearch/index/codec/tsdb/ES87TSDBDocValuesConsumer.java

@@ -125,25 +125,6 @@ private long[] writeField(FieldInfo field, DocValuesProducer valuesProducer, lon
             numValues += count;
         }
 
-        if (numDocsWithValue == 0) { // meta[-2, 0]: No documents with values
-            meta.writeLong(-2); // docsWithFieldOffset
-            meta.writeLong(0L); // docsWithFieldLength
-            meta.writeShort((short) -1); // jumpTableEntryCount
-            meta.writeByte((byte) -1); // denseRankPower
-        } else if (numDocsWithValue == maxDoc) { // meta[-1, 0]: All documents have values
-            meta.writeLong(-1); // docsWithFieldOffset
-            meta.writeLong(0L); // docsWithFieldLength
-            meta.writeShort((short) -1); // jumpTableEntryCount
-            meta.writeByte((byte) -1); // denseRankPower
-        } else { // meta[data.offset, data.length]: IndexedDISI structure for documents with values
-            long offset = data.getFilePointer();
-            meta.writeLong(offset); // docsWithFieldOffset
-            values = valuesProducer.getSortedNumeric(field);
-            final short jumpTableEntryCount = IndexedDISI.writeBitSet(values, data, IndexedDISI.DEFAULT_DENSE_RANK_POWER);
-            meta.writeLong(data.getFilePointer() - offset); // docsWithFieldLength
-            meta.writeShort(jumpTableEntryCount);
-            meta.writeByte(IndexedDISI.DEFAULT_DENSE_RANK_POWER);
-        }
         meta.writeLong(numValues);
         meta.writeInt(numDocsWithValue);
 
@@ -207,6 +188,26 @@ private long[] writeField(FieldInfo field, DocValuesProducer valuesProducer, lon
             meta.writeLong(valuesDataLength);
         }
 
+        if (numDocsWithValue == 0) { // meta[-2, 0]: No documents with values
+            meta.writeLong(-2); // docsWithFieldOffset
+            meta.writeLong(0L); // docsWithFieldLength
+            meta.writeShort((short) -1); // jumpTableEntryCount
+            meta.writeByte((byte) -1); // denseRankPower
+        } else if (numDocsWithValue == maxDoc) { // meta[-1, 0]: All documents have values
+            meta.writeLong(-1); // docsWithFieldOffset
+            meta.writeLong(0L); // docsWithFieldLength
+            meta.writeShort((short) -1); // jumpTableEntryCount
+            meta.writeByte((byte) -1); // denseRankPower
+        } else { // meta[data.offset, data.length]: IndexedDISI structure for documents with values
+            long offset = data.getFilePointer();
+            meta.writeLong(offset); // docsWithFieldOffset
+            values = valuesProducer.getSortedNumeric(field);
+            final short jumpTableEntryCount = IndexedDISI.writeBitSet(values, data, IndexedDISI.DEFAULT_DENSE_RANK_POWER);
+            meta.writeLong(data.getFilePointer() - offset); // docsWithFieldLength
+            meta.writeShort(jumpTableEntryCount);
+            meta.writeByte(IndexedDISI.DEFAULT_DENSE_RANK_POWER);
+        }
+
         return new long[] { numDocsWithValue, numValues };
     }
 

server/src/main/java/org/elasticsearch/index/codec/tsdb/ES87TSDBDocValuesFormat.java

@@ -33,10 +33,14 @@ public class ES87TSDBDocValuesFormat extends org.apache.lucene.codecs.DocValuesF
     static final byte SORTED_SET = 3;
     static final byte SORTED_NUMERIC = 4;
 
-    static final int VERSION_META_MOVE_META_ENTRY = 1;
-    // Move numDocsWithField from SortedNumericEntry to NumericEntry
+    // Version constants:
     static final int VERSION_START = 0;
-    static final int VERSION_CURRENT = VERSION_META_MOVE_META_ENTRY;
+    // Second versions has two changes:
+    // 1) Moved numDocsWithField metadata statistic from SortedNumericEntry to NumericEntry and
+    // 2) Moved docsWithFieldOffset, docsWithFieldLength, jumpTableEntryCount, denseRankPower metadata properties in the format to be after
+    // values metadata.
+    static final int VERSION_TWO = 1;
+    static final int VERSION_CURRENT = VERSION_TWO;
 
     static final int TERMS_DICT_BLOCK_LZ4_SHIFT = 6;
     static final int TERMS_DICT_BLOCK_LZ4_SIZE = 1 << TERMS_DICT_BLOCK_LZ4_SHIFT;

server/src/main/java/org/elasticsearch/index/codec/tsdb/ES87TSDBDocValuesProducer.java

@@ -904,12 +904,14 @@ private static DocValuesSkipperEntry readDocValueSkipperMeta(IndexInput meta) th
     }
 
     private static void readNumeric(IndexInput meta, NumericEntry entry, int version) throws IOException {
-        entry.docsWithFieldOffset = meta.readLong();
-        entry.docsWithFieldLength = meta.readLong();
-        entry.jumpTableEntryCount = meta.readShort();
-        entry.denseRankPower = meta.readByte();
+        if (version < ES87TSDBDocValuesFormat.VERSION_TWO) {
+            entry.docsWithFieldOffset = meta.readLong();
+            entry.docsWithFieldLength = meta.readLong();
+            entry.jumpTableEntryCount = meta.readShort();
+            entry.denseRankPower = meta.readByte();
+        }
         entry.numValues = meta.readLong();
-        if (version >= ES87TSDBDocValuesFormat.VERSION_META_MOVE_META_ENTRY) {
+        if (version >= ES87TSDBDocValuesFormat.VERSION_TWO) {
             entry.numDocsWithField = meta.readInt();
         }
         if (entry.numValues > 0) {
@@ -928,6 +930,12 @@ private static void readNumeric(IndexInput meta, NumericEntry entry, int version
             entry.valuesOffset = meta.readLong();
             entry.valuesLength = meta.readLong();
         }
+        if (version >= ES87TSDBDocValuesFormat.VERSION_TWO) {
+            entry.docsWithFieldOffset = meta.readLong();
+            entry.docsWithFieldLength = meta.readLong();
+            entry.jumpTableEntryCount = meta.readShort();
+            entry.denseRankPower = meta.readByte();
+        }
     }
 
     private BinaryEntry readBinary(IndexInput meta) throws IOException {
@@ -962,7 +970,7 @@ private static SortedNumericEntry readSortedNumeric(IndexInput meta, int version
 
     private static SortedNumericEntry readSortedNumeric(IndexInput meta, SortedNumericEntry entry, int version) throws IOException {
         readNumeric(meta, entry, version);
-        if (version < ES87TSDBDocValuesFormat.VERSION_META_MOVE_META_ENTRY) {
+        if (version < ES87TSDBDocValuesFormat.VERSION_TWO) {
             entry.numDocsWithField = meta.readInt();
         }
         if (entry.numDocsWithField != entry.numValues) {