diff --git a/internal/ccMetric/ccMetric.go b/internal/ccMetric/ccMetric.go
index ae7ab1b..20b9786 100644
--- a/internal/ccMetric/ccMetric.go
+++ b/internal/ccMetric/ccMetric.go
@@ -14,62 +14,73 @@ import (
 //
 // See: https://docs.influxdata.com/influxdb/latest/reference/syntax/line-protocol/
 type ccMetric struct {
-	name   string      // Measurement name
-	tags   []*lp.Tag   // ordered list of of tags
-	fields []*lp.Field // unordered list of of fields
-	tm     time.Time   // timestamp
-	meta   []*lp.Tag   // odered list of meta data tags
+	name   string            // Measurement name
+	meta   map[string]string // map of meta data tags
+	tags   map[string]string // map of of tags
+	fields []*lp.Field       // unordered list of of fields
+	tm     time.Time         // timestamp
 }
 
 // ccmetric access functions
 type CCMetric interface {
-	lp.MutableMetric                         // SetTime, AddTag, AddField
-	AddMeta(key, value string)               // Add a meta data tag
-	MetaList() []*lp.Tag                     // Returns the meta data list
-	RemoveTag(key string)                    // Remove a tag addressed by its key
-	GetTag(key string) (string, bool)        // Get a tag addressed by its key
-	GetMeta(key string) (string, bool)       // Get a meta data tab addressed by its key
+	lp.Metric // Time(), Name(), TagList(), FieldList()
+
+	SetTime(t time.Time)
+
+	Meta() map[string]string           // Map of meta data tags
+	MetaList() []*lp.Tag               // Ordered list of meta data
+	AddMeta(key, value string)         // Add a meta data tag
+	GetMeta(key string) (string, bool) // Get a meta data tab addressed by its key
+
+	Tags() map[string]string          // Map of tags
+	AddTag(key, value string)         // Add a tag
+	GetTag(key string) (string, bool) // Get a tag by its key
+	RemoveTag(key string)             // Remove a tag by its key
+
 	GetField(key string) (interface{}, bool) // Get a field addressed by its key
 	HasField(key string) bool                // Check if a field key is present
 	RemoveField(key string)                  // Remove a field addressed by its key
 }
 
-// Meta returns the list of meta data tags as key-value mapping
+// Meta returns the meta data tags as key-value mapping
 func (m *ccMetric) Meta() map[string]string {
-	meta := make(map[string]string, len(m.meta))
-	for _, m := range m.meta {
-		meta[m.Key] = m.Value
-	}
-	return meta
+	return m.meta
 }
 
-// MetaList returns the list of meta data tags
+// MetaList returns the the list of meta data tags as sorted list of key value tags
 func (m *ccMetric) MetaList() []*lp.Tag {
-	return m.meta
+
+	ml := make([]*lp.Tag, 0, len(m.meta))
+	for key, value := range m.meta {
+		ml = append(ml, &lp.Tag{Key: key, Value: value})
+	}
+	sort.Slice(ml, func(i, j int) bool { return ml[i].Key < ml[j].Key })
+	return ml
 }
 
 // String implements the stringer interface for data type ccMetric
 func (m *ccMetric) String() string {
-	return fmt.Sprintf("%s %v %v %v %d", m.name, m.Tags(), m.Meta(), m.Fields(), m.tm.UnixNano())
+	return fmt.Sprintf("%s %v %v %v %d", m.name, m.tags, m.meta, m.Fields(), m.tm.UnixNano())
 }
 
-// Name returns the metric name
+// Name returns the measurement name
 func (m *ccMetric) Name() string {
 	return m.name
 }
 
 // Tags returns the the list of tags as key-value-mapping
 func (m *ccMetric) Tags() map[string]string {
-	tags := make(map[string]string, len(m.tags))
-	for _, tag := range m.tags {
-		tags[tag.Key] = tag.Value
-	}
-	return tags
+	return m.tags
 }
 
-// TagList returns the list of tags
+// TagList returns the the list of tags as sorted list of key value tags
 func (m *ccMetric) TagList() []*lp.Tag {
-	return m.tags
+	tl := make([]*lp.Tag, 0, len(m.tags))
+	for key, value := range m.tags {
+		tl = append(tl, &lp.Tag{Key: key, Value: value})
+	}
+	sort.Slice(tl, func(i, j int) bool { return tl[i].Key < tl[j].Key })
+	return tl
 }
 
 // Fields returns the list of fields as key-value-mapping
@@ -99,112 +110,50 @@ func (m *ccMetric) SetTime(t time.Time) {
 
 // HasTag checks if a tag with key equal to <key> is present in the list of tags
 func (m *ccMetric) HasTag(key string) bool {
-	for _, tag := range m.tags {
-		if tag.Key == key {
-			return true
-		}
-	}
-	return false
+	_, ok := m.tags[key]
+	return ok
 }
 
 // GetTag returns the tag with tag's key equal to <key>
 func (m *ccMetric) GetTag(key string) (string, bool) {
-	for _, tag := range m.tags {
-		if tag.Key == key {
-			return tag.Value, true
-		}
-	}
-	return "", false
+	value, ok := m.tags[key]
+	return value, ok
 }
 
 // RemoveTag removes the tag with tag's key equal to <key>
 // and keeps the tag list ordered by the keys
 func (m *ccMetric) RemoveTag(key string) {
-	for i, tag := range m.tags {
-		if tag.Key == key {
-			copy(m.tags[i:], m.tags[i+1:])
-			m.tags[len(m.tags)-1] = nil
-			m.tags = m.tags[:len(m.tags)-1]
-			return
-		}
-	}
+	delete(m.tags, key)
 }
 
 // AddTag adds a tag (consisting of key and value)
 // and keeps the tag list ordered by the keys
 func (m *ccMetric) AddTag(key, value string) {
-	for i, tag := range m.tags {
-		if key > tag.Key {
-			continue
-		}
-
-		if key == tag.Key {
-			tag.Value = value
-			return
-		}
-
-		m.tags = append(m.tags, nil)
-		copy(m.tags[i+1:], m.tags[i:])
-		m.tags[i] = &lp.Tag{Key: key, Value: value}
-		return
-	}
-
-	m.tags = append(m.tags, &lp.Tag{Key: key, Value: value})
+	m.tags[key] = value
 }
 
 // HasTag checks if a meta data tag with meta data's key equal to <key> is present in the list of meta data tags
 func (m *ccMetric) HasMeta(key string) bool {
-	for _, tag := range m.meta {
-		if tag.Key == key {
-			return true
-		}
-	}
-	return false
+	_, ok := m.meta[key]
+	return ok
 }
 
 // GetMeta returns the meta data tag with meta data's key equal to <key>
 func (m *ccMetric) GetMeta(key string) (string, bool) {
-	for _, tag := range m.meta {
-		if tag.Key == key {
-			return tag.Value, true
-		}
-	}
-	return "", false
+	value, ok := m.meta[key]
+	return value, ok
 }
 
 // RemoveMeta removes the meta data tag with tag's key equal to <key>
 // and keeps the meta data tag list ordered by the keys
 func (m *ccMetric) RemoveMeta(key string) {
-	for i, tag := range m.meta {
-		if tag.Key == key {
-			copy(m.meta[i:], m.meta[i+1:])
-			m.meta[len(m.meta)-1] = nil
-			m.meta = m.meta[:len(m.meta)-1]
-			return
-		}
-	}
+	delete(m.meta, key)
 }
 
 // AddMeta adds a meta data tag (consisting of key and value)
 // and keeps the meta data list ordered by the keys
 func (m *ccMetric) AddMeta(key, value string) {
-	for i, tag := range m.meta {
-		if key > tag.Key {
-			continue
-		}
-
-		if key == tag.Key {
-			tag.Value = value
-			return
-		}
-
-		m.meta = append(m.meta, nil)
-		copy(m.meta[i+1:], m.meta[i:])
-		m.meta[i] = &lp.Tag{Key: key, Value: value}
-		return
-	}
-
-	m.meta = append(m.meta, &lp.Tag{Key: key, Value: value})
+	m.meta[key] = value
 }
 
 // AddField adds a field (consisting of key and value) to the unordered list of fields
@@ -261,62 +210,49 @@ func New(
 ) (CCMetric, error) {
 	m := &ccMetric{
 		name:   name,
-		tags:   nil,
-		fields: nil,
+		tags:   make(map[string]string, len(tags)),
+		meta:   make(map[string]string, len(meta)),
+		fields: make([]*lp.Field, 0, len(fields)),
 		tm:     tm,
-		meta:   nil,
 	}
 
-	// Sorted list of tags
-	if len(tags) > 0 {
-		m.tags = make([]*lp.Tag, 0, len(tags))
-		for k, v := range tags {
-			m.tags = append(m.tags,
-				&lp.Tag{Key: k, Value: v})
-		}
-		sort.Slice(m.tags, func(i, j int) bool { return m.tags[i].Key < m.tags[j].Key })
+	// deep copy tags
+	for k, v := range tags {
+		m.tags[k] = v
 	}
 
-	// Sorted list of meta data tags
-	if len(meta) > 0 {
-		m.meta = make([]*lp.Tag, 0, len(meta))
-		for k, v := range meta {
-			m.meta = append(m.meta,
-				&lp.Tag{Key: k, Value: v})
-		}
-		sort.Slice(m.meta, func(i, j int) bool { return m.meta[i].Key < m.meta[j].Key })
+	// deep copy meta data tags
+	for k, v := range meta {
+		m.meta[k] = v
 	}
 
 	// Unsorted list of fields
-	if len(fields) > 0 {
-		m.fields = make([]*lp.Field, 0, len(fields))
-		for k, v := range fields {
-			v := convertField(v)
-			if v == nil {
-				continue
-			}
-			m.AddField(k, v)
+	for k, v := range fields {
+		v := convertField(v)
+		if v == nil {
+			continue
 		}
+		m.AddField(k, v)
 	}
 
 	return m, nil
 }
 
 // FromMetric copies the metric <other>
-func FromMetric(other CCMetric) CCMetric {
+func FromMetric(other ccMetric) CCMetric {
 	m := &ccMetric{
 		name:   other.Name(),
-		tags:   make([]*lp.Tag, len(other.TagList())),
+		tags:   make(map[string]string),
 		fields: make([]*lp.Field, len(other.FieldList())),
-		meta:   make([]*lp.Tag, len(other.MetaList())),
+		meta:   make(map[string]string),
 		tm:     other.Time(),
 	}
 
-	for i, tag := range other.TagList() {
-		m.tags[i] = &lp.Tag{Key: tag.Key, Value: tag.Value}
+	for key, value := range other.Tags() {
+		m.tags[key] = value
 	}
-	for i, s := range other.MetaList() {
-		m.meta[i] = &lp.Tag{Key: s.Key, Value: s.Value}
+	for key, value := range other.Meta() {
+		m.meta[key] = value
 	}
 
 	for i, field := range other.FieldList() {
@@ -329,17 +265,14 @@ func FromMetric(other CCMetric) CCMetric {
 func FromInfluxMetric(other lp.Metric) CCMetric {
 	m := &ccMetric{
 		name:   other.Name(),
-		tags:   make([]*lp.Tag, len(other.TagList())),
+		tags:   make(map[string]string),
 		fields: make([]*lp.Field, len(other.FieldList())),
-		meta:   make([]*lp.Tag, 0),
+		meta:   make(map[string]string),
 		tm:     other.Time(),
 	}
 
-	for i, otherTag := range other.TagList() {
-		m.tags[i] = &lp.Tag{
-			Key:   otherTag.Key,
-			Value: otherTag.Value,
-		}
+	for _, otherTag := range other.TagList() {
+		m.tags[otherTag.Key] = otherTag.Value
 	}
 
 	for i, otherField := range other.FieldList() {
diff --git a/internal/metricRouter/metricRouter.go b/internal/metricRouter/metricRouter.go
index 870af02..83c14e7 100644
--- a/internal/metricRouter/metricRouter.go
+++ b/internal/metricRouter/metricRouter.go
@@ -141,11 +141,11 @@ func (r *metricRouter) EvalCondition(cond string, point lp.CCMetric) (bool, erro
 	// Add metric name, tags, meta data, fields and timestamp to the parameter list
 	params := make(map[string]interface{})
 	params["name"] = point.Name()
-	for _, t := range point.TagList() {
-		params[t.Key] = t.Value
+	for key, value := range point.Tags() {
+		params[key] = value
 	}
-	for _, m := range point.MetaList() {
-		params[m.Key] = m.Value
+	for key, value := range point.Meta() {
+		params[key] = value
 	}
 	for _, f := range point.FieldList() {
 		params[f.Key] = f.Value
diff --git a/sinks/gangliaSink.go b/sinks/gangliaSink.go
index 87506a0..3fd48e7 100644
--- a/sinks/gangliaSink.go
+++ b/sinks/gangliaSink.go
@@ -30,16 +30,16 @@ func (s *GangliaSink) Write(point lp.CCMetric) error {
 	var err error = nil
 	var tagsstr []string
 	var argstr []string
-	for _, t := range point.TagList() {
-		switch t.Key {
+	for key, value := range point.Tags() {
+		switch key {
 		case "cluster":
-			argstr = append(argstr, fmt.Sprintf("--cluster=%s", t.Value))
+			argstr = append(argstr, fmt.Sprintf("--cluster=%s", value))
 		case "unit":
-			argstr = append(argstr, fmt.Sprintf("--units=%s", t.Value))
+			argstr = append(argstr, fmt.Sprintf("--units=%s", value))
 		case "group":
-			argstr = append(argstr, fmt.Sprintf("--group=%s", t.Value))
+			argstr = append(argstr, fmt.Sprintf("--group=%s", value))
 		default:
-			tagsstr = append(tagsstr, fmt.Sprintf("%s=%s", t.Key, t.Value))
+			tagsstr = append(tagsstr, fmt.Sprintf("%s=%s", key, value))
 		}
 	}
 	if len(tagsstr) > 0 {
diff --git a/sinks/influxSink.go b/sinks/influxSink.go
index dca1572..7313490 100644
--- a/sinks/influxSink.go
+++ b/sinks/influxSink.go
@@ -5,10 +5,11 @@ import (
 	"crypto/tls"
 	"errors"
 	"fmt"
+	"log"
+
 	lp "github.com/ClusterCockpit/cc-metric-collector/internal/ccMetric"
 	influxdb2 "github.com/influxdata/influxdb-client-go/v2"
 	influxdb2Api "github.com/influxdata/influxdb-client-go/v2/api"
-	"log"
 )
 
 type InfluxSink struct {
@@ -61,12 +62,12 @@ func (s *InfluxSink) Init(config sinkConfig) error {
 func (s *InfluxSink) Write(point lp.CCMetric) error {
 	tags := map[string]string{}
 	fields := map[string]interface{}{}
-	for _, t := range point.TagList() {
-		tags[t.Key] = t.Value
+	for key, value := range point.Tags() {
+		tags[key] = value
 	}
 	if s.meta_as_tags {
-		for _, m := range point.MetaList() {
-			tags[m.Key] = m.Value
+		for key, value := range point.Meta() {
+			tags[key] = value
 		}
 	}
 	for _, f := range point.FieldList() {