base load graph x-axis on data, not a hardcoded window

render/detailed_node.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"sort"
 	"strconv"
-	"time"
 
 	"github.com/weaveworks/scope/probe/docker"
 	"github.com/weaveworks/scope/probe/host"
@@ -496,10 +495,7 @@ func getDockerLabelRows(nmd report.Node) []Row {
 
 func hostOriginTable(nmd report.Node) (Table, bool) {
 	// Ensure that all metrics have the same max
-	var (
-		maxLoad  = 0.0
-		lastLoad time.Time
-	)
+	maxLoad := 0.0
 	for _, key := range []string{host.Load1, host.Load5, host.Load15} {
 		if metric, ok := nmd.Metrics[key]; ok {
 			if metric.Len() == 0 {
@@ -508,9 +504,6 @@ func hostOriginTable(nmd report.Node) (Table, bool) {
 			if metric.Max > maxLoad {
 				maxLoad = metric.Max
 			}
-			if lastLoad.IsZero() || metric.Last.After(lastLoad) {
-				lastLoad = metric.Last
-			}
 		}
 	}
 
@@ -522,8 +515,6 @@ func hostOriginTable(nmd report.Node) (Table, bool) {
 	} {
 		if val, ok := nmd.Metrics[tuple.key]; ok {
 			val.Max = maxLoad
-			val.First = lastLoad.Add(-15 * time.Second) // TODO(paulbellamy): This should be based on the duration flag, maybe? or just auto-scale to data.
-			val.Last = lastLoad
 			rows = append(rows, sparklineRow(tuple.human, val, nil))
 		}
 	}