diff --git a/vendor/github.com/armon/go-metrics/.travis.yml b/vendor/github.com/armon/go-metrics/.travis.yml
new file mode 100644
index 0000000..87d230c
--- /dev/null
+++ b/vendor/github.com/armon/go-metrics/.travis.yml
@@ -0,0 +1,13 @@
+language: go
+
+go:
+  - "1.x"
+
+env:
+  - GO111MODULE=on
+
+install:
+  - go get ./...
+
+script:
+  - go test ./...
diff --git a/vendor/github.com/armon/go-metrics/go.mod b/vendor/github.com/armon/go-metrics/go.mod
new file mode 100644
index 0000000..88e1e98
--- /dev/null
+++ b/vendor/github.com/armon/go-metrics/go.mod
@@ -0,0 +1,16 @@
+module github.com/armon/go-metrics
+
+go 1.12
+
+require (
+	github.com/DataDog/datadog-go v2.2.0+incompatible
+	github.com/circonus-labs/circonus-gometrics v2.3.1+incompatible
+	github.com/circonus-labs/circonusllhist v0.1.3 // indirect
+	github.com/hashicorp/go-immutable-radix v1.0.0
+	github.com/hashicorp/go-retryablehttp v0.5.3 // indirect
+	github.com/pascaldekloe/goe v0.1.0
+	github.com/pkg/errors v0.8.1 // indirect
+	github.com/prometheus/client_golang v0.9.2
+	github.com/stretchr/testify v1.3.0 // indirect
+	github.com/tv42/httpunix v0.0.0-20150427012821-b75d8614f926 // indirect
+)
diff --git a/vendor/github.com/armon/go-metrics/go.sum b/vendor/github.com/armon/go-metrics/go.sum
new file mode 100644
index 0000000..5ffd832
--- /dev/null
+++ b/vendor/github.com/armon/go-metrics/go.sum
@@ -0,0 +1,46 @@
+github.com/DataDog/datadog-go v2.2.0+incompatible h1:V5BKkxACZLjzHjSgBbr2gvLA2Ae49yhc6CSY7MLy5k4=
+github.com/DataDog/datadog-go v2.2.0+incompatible/go.mod h1:LButxg5PwREeZtORoXG3tL4fMGNddJ+vMq1mwgfaqoQ=
+github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973 h1:xJ4a3vCFaGF/jqvzLMYoU8P317H5OQ+Via4RmuPwCS0=
+github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
+github.com/circonus-labs/circonus-gometrics v2.3.1+incompatible h1:C29Ae4G5GtYyYMm1aztcyj/J5ckgJm2zwdDajFbx1NY=
+github.com/circonus-labs/circonus-gometrics v2.3.1+incompatible/go.mod h1:nmEj6Dob7S7YxXgwXpfOuvO54S+tGdZdw9fuRZt25Ag=
+github.com/circonus-labs/circonusllhist v0.1.3 h1:TJH+oke8D16535+jHExHj4nQvzlZrj7ug5D7I/orNUA=
+github.com/circonus-labs/circonusllhist v0.1.3/go.mod h1:kMXHVDlOchFAehlya5ePtbp5jckzBHf4XRpQvBOLI+I=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/hashicorp/go-cleanhttp v0.5.0 h1:wvCrVc9TjDls6+YGAF2hAifE1E5U1+b4tH6KdvN3Gig=
+github.com/hashicorp/go-cleanhttp v0.5.0/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80=
+github.com/hashicorp/go-immutable-radix v1.0.0 h1:AKDB1HM5PWEA7i4nhcpwOrO2byshxBjXVn/J/3+z5/0=
+github.com/hashicorp/go-immutable-radix v1.0.0/go.mod h1:0y9vanUI8NX6FsYoO3zeMjhV/C5i9g4Q3DwcSNZ4P60=
+github.com/hashicorp/go-retryablehttp v0.5.3 h1:QlWt0KvWT0lq8MFppF9tsJGF+ynG7ztc2KIPhzRGk7s=
+github.com/hashicorp/go-retryablehttp v0.5.3/go.mod h1:9B5zBasrRhHXnJnui7y6sL7es7NDiJgTc6Er0maI1Xs=
+github.com/hashicorp/go-uuid v1.0.0 h1:RS8zrF7PhGwyNPOtxSClXXj9HA8feRnJzgnI1RJCSnM=
+github.com/hashicorp/go-uuid v1.0.0/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
+github.com/hashicorp/golang-lru v0.5.0 h1:CL2msUPvZTLb5O648aiLNJw3hnBxN2+1Jq8rCOH9wdo=
+github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
+github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
+github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
+github.com/pascaldekloe/goe v0.1.0 h1:cBOtyMzM9HTpWjXfbbunk26uA6nG3a8n06Wieeh0MwY=
+github.com/pascaldekloe/goe v0.1.0/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/prometheus/client_golang v0.9.2 h1:awm861/B8OKDd2I/6o1dy3ra4BamzKhYOiGItCeZ740=
+github.com/prometheus/client_golang v0.9.2/go.mod h1:OsXs2jCmiKlQ1lTBmv21f2mNfw4xf/QclQDMrYNZzcM=
+github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910 h1:idejC8f05m9MGOsuEi1ATq9shN03HrxNkD/luQvxCv8=
+github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
+github.com/prometheus/common v0.0.0-20181126121408-4724e9255275 h1:PnBWHBf+6L0jOqq0gIVUe6Yk0/QMZ640k6NvkxcBf+8=
+github.com/prometheus/common v0.0.0-20181126121408-4724e9255275/go.mod h1:daVV7qP5qjZbuso7PdcryaAu0sAZbrN9i7WWcTMWvro=
+github.com/prometheus/procfs v0.0.0-20181204211112-1dc9a6cbc91a h1:9a8MnZMP0X2nLJdBg+pBmGgkJlSaKC2KaQmTCk1XDtE=
+github.com/prometheus/procfs v0.0.0-20181204211112-1dc9a6cbc91a/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/tv42/httpunix v0.0.0-20150427012821-b75d8614f926 h1:G3dpKMzFDjgEh2q1Z7zUUtKa8ViPtH+ocF0bE0g00O8=
+github.com/tv42/httpunix v0.0.0-20150427012821-b75d8614f926/go.mod h1:9ESjWnEqriFuLhtthL60Sar/7RFoluCcXsuvEwTV5KM=
+golang.org/x/net v0.0.0-20181201002055-351d144fa1fc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/sync v0.0.0-20181108010431-42b317875d0f h1:Bl/8QSvNqXvPGPGXa2z5xUTmV7VDcZyvRZ+QQXkXTZQ=
+golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
diff --git a/vendor/github.com/armon/go-metrics/inmem.go b/vendor/github.com/armon/go-metrics/inmem.go
index 4e2d6a7..93b0e0a 100644
--- a/vendor/github.com/armon/go-metrics/inmem.go
+++ b/vendor/github.com/armon/go-metrics/inmem.go
@@ -255,11 +255,11 @@
 	}
 	copyCurrent.Counters = make(map[string]SampledValue, len(current.Counters))
 	for k, v := range current.Counters {
-		copyCurrent.Counters[k] = v
+		copyCurrent.Counters[k] = v.deepCopy()
 	}
 	copyCurrent.Samples = make(map[string]SampledValue, len(current.Samples))
 	for k, v := range current.Samples {
-		copyCurrent.Samples[k] = v
+		copyCurrent.Samples[k] = v.deepCopy()
 	}
 	current.RUnlock()
 
diff --git a/vendor/github.com/armon/go-metrics/inmem_endpoint.go b/vendor/github.com/armon/go-metrics/inmem_endpoint.go
index 504f1b3..5fac958 100644
--- a/vendor/github.com/armon/go-metrics/inmem_endpoint.go
+++ b/vendor/github.com/armon/go-metrics/inmem_endpoint.go
@@ -41,6 +41,16 @@
 	DisplayLabels map[string]string `json:"Labels"`
 }
 
+// deepCopy allocates a new instance of AggregateSample
+func (source *SampledValue) deepCopy() SampledValue {
+	dest := *source
+	if source.AggregateSample != nil {
+		dest.AggregateSample = &AggregateSample{}
+		*dest.AggregateSample = *source.AggregateSample
+	}
+	return dest
+}
+
 // DisplayMetrics returns a summary of the metrics from the most recent finished interval.
 func (i *InmemSink) DisplayMetrics(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
 	data := i.Data()
@@ -52,12 +62,15 @@
 		return nil, fmt.Errorf("no metric intervals have been initialized yet")
 	case n == 1:
 		// Show the current interval if it's all we have
-		interval = i.intervals[0]
+		interval = data[0]
 	default:
 		// Show the most recent finished interval if we have one
-		interval = i.intervals[n-2]
+		interval = data[n-2]
 	}
 
+	interval.RLock()
+	defer interval.RUnlock()
+
 	summary := MetricsSummary{
 		Timestamp: interval.Interval.Round(time.Second).UTC().String(),
 		Gauges:    make([]GaugeValue, 0, len(interval.Gauges)),
diff --git a/vendor/github.com/armon/go-metrics/metrics.go b/vendor/github.com/armon/go-metrics/metrics.go
index cf9def7..4920d68 100644
--- a/vendor/github.com/armon/go-metrics/metrics.go
+++ b/vendor/github.com/armon/go-metrics/metrics.go
@@ -197,7 +197,7 @@
 	if labels == nil {
 		return nil
 	}
-	toReturn := labels[:0]
+	toReturn := []Label{}
 	for _, label := range labels {
 		if m.labelIsAllowed(&label) {
 			toReturn = append(toReturn, label)