From b62ca996f63e64dad76bdd95c7d8b4f31d4d6f0a Mon Sep 17 00:00:00 2001
From: Steve Yen <steve.yen@gmail.com>
Date: Tue, 6 Mar 2018 13:30:44 -0800
Subject: [PATCH] scorch zap optimize chunkedIntCoder.Add() calls to use
 multiple vals

This change leverages the ability for the chunkedIntCoder.Add() method
to accept multiple input param values (via the '...' param signature),
meaning there are fewer Add() invocations.
---
 index/scorch/segment/zap/build.go | 53 ++++++-------------------------
 1 file changed, 9 insertions(+), 44 deletions(-)

diff --git a/index/scorch/segment/zap/build.go b/index/scorch/segment/zap/build.go
index 237cc5f3..361e56e5 100644
--- a/index/scorch/segment/zap/build.go
+++ b/index/scorch/segment/zap/build.go
@@ -319,19 +319,10 @@ func persistPostingDetails(memSegment *mem.Segment, w *CountHashWriter, chunkFac
 		postingsListItr := memSegment.Postings[postingID].Iterator()
 		var offset int
 		for postingsListItr.HasNext() {
-
 			docNum := uint64(postingsListItr.Next())
 
-			// put freq
-			err := tfEncoder.Add(docNum, freqs[offset])
-			if err != nil {
-				return nil, nil, err
-			}
-
-			// put norm
-			norm := norms[offset]
-			normBits := math.Float32bits(norm)
-			err = tfEncoder.Add(docNum, uint64(normBits))
+			// put freq & norm
+			err := tfEncoder.Add(docNum, freqs[offset], uint64(math.Float32bits(norms[offset])))
 			if err != nil {
 				return nil, nil, err
 			}
@@ -347,7 +338,6 @@ func persistPostingDetails(memSegment *mem.Segment, w *CountHashWriter, chunkFac
 		if err != nil {
 			return nil, nil, err
 		}
-
 	}
 
 	// now do it again for the locations
@@ -371,43 +361,17 @@ func persistPostingDetails(memSegment *mem.Segment, w *CountHashWriter, chunkFac
 			n := int(freqs[offset])
 			for i := 0; i < n; i++ {
 				if len(locfields) > 0 {
-					// put field
-					err := locEncoder.Add(docNum, uint64(locfields[locOffset]))
-					if err != nil {
-						return nil, nil, err
-					}
-
-					// put pos
-					err = locEncoder.Add(docNum, locpos[locOffset])
-					if err != nil {
-						return nil, nil, err
-					}
-
-					// put start
-					err = locEncoder.Add(docNum, locstarts[locOffset])
-					if err != nil {
-						return nil, nil, err
-					}
-
-					// put end
-					err = locEncoder.Add(docNum, locends[locOffset])
-					if err != nil {
-						return nil, nil, err
-					}
-
-					// put the number of array positions to follow
-					num := len(locarraypos[locOffset])
-					err = locEncoder.Add(docNum, uint64(num))
+					err := locEncoder.Add(docNum, uint64(locfields[locOffset]),
+						locpos[locOffset], locstarts[locOffset], locends[locOffset],
+						uint64(len(locarraypos[locOffset])))
 					if err != nil {
 						return nil, nil, err
 					}
 
 					// put each array position
-					for _, pos := range locarraypos[locOffset] {
-						err = locEncoder.Add(docNum, pos)
-						if err != nil {
-							return nil, nil, err
-						}
+					err = locEncoder.Add(docNum, locarraypos[locOffset]...)
+					if err != nil {
+						return nil, nil, err
 					}
 				}
 				locOffset++
@@ -417,6 +381,7 @@ func persistPostingDetails(memSegment *mem.Segment, w *CountHashWriter, chunkFac
 
 		// record where this postings loc info starts
 		locOffsets = append(locOffsets, uint64(w.Count()))
+
 		locEncoder.Close()
 		_, err := locEncoder.Write(w)
 		if err != nil {