minor cache delete improvements

Author: replay

mdata/cache/ccache.go

@@ -183,13 +183,10 @@ func (c *CCache) evict(target *accnt.EvictTarget) {
 	if length == 0 {
 		delete(c.metricCache, target.Metric)
 
-		if ccms, ok := c.metricRawKeys[ccm.RawMetric]; ok {
-			if _, ok := ccms[ccm.Cons]; ok {
-				delete(ccms, ccm.Cons)
-				if len(ccms) == 0 {
-					delete(c.metricRawKeys, ccm.RawMetric)
-				}
-			}
+		// this key should alway be present, if not there there is a corruption of the state
+		delete(c.metricRawKeys[ccm.RawMetric], ccm.Cons)
+		if len(c.metricRawKeys[ccm.RawMetric]) == 0 {
+			delete(c.metricRawKeys, ccm.RawMetric)
 		}
 	}
 }

mdata/cache/ccache_metric.go

@@ -48,11 +48,16 @@ func (mc *CCacheMetric) Del(ts uint32) int {
 	prev := mc.chunks[ts].Prev
 	next := mc.chunks[ts].Next
 
-	if _, ok := mc.chunks[prev]; prev != 0 && ok {
-		mc.chunks[prev].Next = 0
+	if prev != 0 {
+		if _, ok := mc.chunks[prev]; ok {
+			mc.chunks[prev].Next = 0
+		}
 	}
-	if _, ok := mc.chunks[next]; next != 0 && ok {
-		mc.chunks[next].Prev = 0
+
+	if next != 0 {
+		if _, ok := mc.chunks[next]; ok {
+			mc.chunks[next].Prev = 0
+		}
 	}
 
 	delete(mc.chunks, ts)