Introduce translog no-op (iteration)

Author: jasontedor

core/src/main/java/org/elasticsearch/common/io/stream/StreamOutput.java

@@ -223,11 +223,6 @@ public void writeVLong(long i) throws IOException {
         writeByte((byte) i);
     }
 
-    public static int lengthVLong(long i) {
-        assert i >= 0;
-        return 1 + (int) Math.floor(Math.log(i) / Math.log(2)) / 7;
-    }
-
     /**
      * Writes a long in a variable-length format. Writes between one and ten bytes.
      * Values are remapped by sliding the sign bit into the lsb and then encoded as an unsigned number
@@ -333,7 +328,7 @@ public void writeString(String str) throws IOException {
             // make sure any possible char can fit into the buffer in any possible iteration
             // we need at most 3 bytes so we flush the buffer once we have less than 3 bytes
             // left before we start another iteration
-            if (offset > buffer.length-3) {
+            if (offset > buffer.length - 3) {
                 writeBytes(buffer, offset);
                 offset = 0;
             }

core/src/main/java/org/elasticsearch/index/engine/Engine.java

@@ -1172,7 +1172,7 @@ TYPE operationType() {
 
         @Override
         public int estimatedSizeInBytes() {
-            return 2 * reason.length() + StreamOutput.lengthVLong(seqNo()) + StreamOutput.lengthVLong(primaryTerm());
+            return 2 * reason.length() + 2 * Long.BYTES;
         }
 
     }

core/src/main/java/org/elasticsearch/index/translog/Translog.java

@@ -862,8 +862,8 @@ public Index(StreamInput in) throws IOException {
                 this.autoGeneratedIdTimestamp = IndexRequest.UNSET_AUTO_GENERATED_TIMESTAMP;
             }
             if (format >= FORMAT_SEQ_NO) {
-                seqNo = in.readVLong();
-                primaryTerm = in.readVLong();
+                seqNo = in.readLong();
+                primaryTerm = in.readLong();
             }
         }
 
@@ -955,8 +955,8 @@ public void writeTo(StreamOutput out) throws IOException {
 
             out.writeByte(versionType.getValue());
             out.writeLong(autoGeneratedIdTimestamp);
-            out.writeVLong(seqNo);
-            out.writeVLong(primaryTerm);
+            out.writeLong(seqNo);
+            out.writeLong(primaryTerm);
         }
 
         @Override
@@ -1160,8 +1160,8 @@ public String reason() {
         }
 
         NoOp(final StreamInput in) throws IOException {
-            seqNo = in.readVLong();
-            primaryTerm = in.readVLong();
+            seqNo = in.readLong();
+            primaryTerm = in.readLong();
             reason = in.readString();
         }
 
@@ -1176,8 +1176,8 @@ public NoOp(final long seqNo, final long primaryTerm, final String reason) {
 
         @Override
         public void writeTo(StreamOutput out) throws IOException {
-            out.writeVLong(seqNo);
-            out.writeVLong(primaryTerm);
+            out.writeLong(seqNo);
+            out.writeLong(primaryTerm);
             out.writeString(reason);
         }
 
@@ -1188,7 +1188,7 @@ public Type opType() {
 
         @Override
         public long estimateSize() {
-            return 2 * reason.length() + StreamOutput.lengthVLong(seqNo) + StreamOutput.lengthVLong(primaryTerm);
+            return 2 * reason.length() + 2 * Long.BYTES;
         }
 
         @Override

core/src/test/java/org/elasticsearch/index/translog/TranslogTests.java

@@ -318,12 +318,10 @@ public void testStats() throws IOException {
         {
             final TranslogStats stats = stats();
             assertThat(stats.estimatedNumberOfOperations(), equalTo(4L));
-            assertThat(
-                stats.getTranslogSizeInBytes(),
-                equalTo(165L + StreamOutput.lengthVLong(seqNo) + StreamOutput.lengthVLong(primaryTerm)));
+            assertThat(stats.getTranslogSizeInBytes(), equalTo(181L));
         }
 
-        final long expectedSizeInBytes = 208L + StreamOutput.lengthVLong(seqNo) + StreamOutput.lengthVLong(primaryTerm);
+        final long expectedSizeInBytes = 224L;
         translog.prepareCommit();
         {
             final TranslogStats stats = stats();
@@ -359,6 +357,24 @@ public void testStats() throws IOException {
         }
     }
 
+    public void testTotalTests() {
+        final TranslogStats total = new TranslogStats();
+        final int n = randomIntBetween(0, 16);
+        final List<TranslogStats> statsList = new ArrayList<>(n);
+        for (int i = 0; i < n; i++) {
+            final TranslogStats stats = new TranslogStats(randomIntBetween(1, 4096), randomIntBetween(1, 1 << 20));
+            statsList.add(stats);
+            total.add(stats);
+        }
+
+        assertThat(
+            total.estimatedNumberOfOperations(),
+            equalTo(statsList.stream().mapToLong(TranslogStats::estimatedNumberOfOperations).sum()));
+        assertThat(
+            total.getTranslogSizeInBytes(),
+            equalTo(statsList.stream().mapToLong(TranslogStats::getTranslogSizeInBytes).sum()));
+    }
+
     public void testNegativeNumberOfOperations() {
         final IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> new TranslogStats(-1, 1));
         assertThat(e, hasToString(containsString("numberOfOperations must be >= 0")));