From 0920972f795bb7847992e9cb66703259465b3861 Mon Sep 17 00:00:00 2001
From: Brian Brazil <brian.brazil@robustperception.io>
Date: Tue, 16 May 2017 15:12:40 +0100
Subject: [PATCH] Initilise scraped sample map, and rename to series map.

---
 retrieval/scrape.go | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/retrieval/scrape.go b/retrieval/scrape.go
index 0d67276ffe..0135bd9b09 100644
--- a/retrieval/scrape.go
+++ b/retrieval/scrape.go
@@ -427,9 +427,9 @@ type scrapeLoop struct {
 	reportAppender func() storage.Appender
 
 	// TODO: Keep only the values from the last scrape to avoid a memory leak.
-	refCache                map[string]uint64         // Parsed string to ref.
-	lsetCache               map[uint64]lsetCacheEntry // Ref to labelset and string
-	samplesInPreviousScrape map[string]labels.Labels
+	refCache               map[string]uint64         // Parsed string to ref.
+	lsetCache              map[uint64]lsetCacheEntry // Ref to labelset and string
+	seriesInPreviousScrape map[string]labels.Labels
 
 	ctx       context.Context
 	scrapeCtx context.Context
@@ -503,8 +503,8 @@ mainLoop:
 		if err == nil {
 			b = buf.Bytes()
 		} else if errc != nil {
-      errc <- err
-    }
+			errc <- err
+		}
 		// A failed scrape is the same as an empty scrape,
 		// we still call sl.append to trigger stale markers.
 		if total, added, err = sl.append(b, start); err != nil {
@@ -612,12 +612,12 @@ func (s samples) Less(i, j int) bool {
 
 func (sl *scrapeLoop) append(b []byte, ts time.Time) (total, added int, err error) {
 	var (
-		app            = sl.appender()
-		p              = textparse.New(b)
-		defTime        = timestamp.FromTime(ts)
-		samplesScraped = map[string]labels.Labels{}
-		numOutOfOrder  = 0
-		numDuplicates  = 0
+		app           = sl.appender()
+		p             = textparse.New(b)
+		defTime       = timestamp.FromTime(ts)
+		seriesScraped = make(map[string]labels.Labels, len(sl.seriesInPreviousScrape))
+		numOutOfOrder = 0
+		numDuplicates = 0
 	)
 
 loop:
@@ -635,7 +635,7 @@ loop:
 		if ok {
 			switch err = app.AddFast(ref, t, v); err {
 			case nil:
-				samplesScraped[sl.lsetCache[ref].str] = sl.lsetCache[ref].lset
+				seriesScraped[sl.lsetCache[ref].str] = sl.lsetCache[ref].lset
 			case storage.ErrNotFound:
 				ok = false
 			case errSeriesDropped:
@@ -683,7 +683,7 @@ loop:
 			sl.lsetCache[ref] = lsetCacheEntry{lset: lset, str: str}
 			if tp == nil {
 				// Bypass staleness logic if there is an explicit timestamp.
-				samplesScraped[str] = lset
+				seriesScraped[str] = lset
 			}
 		}
 		added++
@@ -698,9 +698,9 @@ loop:
 		sl.l.With("numDropped", numDuplicates).Warn("Error on ingesting samples with different value but same timestamp")
 	}
 	if err == nil {
-		for metric, lset := range sl.samplesInPreviousScrape {
-			if _, ok := samplesScraped[metric]; !ok {
-				// Sample no longer exposed, mark it stale.
+		for metric, lset := range sl.seriesInPreviousScrape {
+			if _, ok := seriesScraped[metric]; !ok {
+				// Series no longer exposed, mark it stale.
 				_, err = app.Add(lset, defTime, math.Float64frombits(value.StaleNaN))
 				switch err {
 				case nil:
@@ -725,7 +725,7 @@ loop:
 	if err := app.Commit(); err != nil {
 		return total, 0, err
 	}
-	sl.samplesInPreviousScrape = samplesScraped
+	sl.seriesInPreviousScrape = seriesScraped
 	return total, added, nil
 }