metrics: pull library and introduce ResettingTimer and InfluxDB reporter (#15910)

* go-metrics: fork library and introduce ResettingTimer and InfluxDB reporter.

* vendor: change nonsense/go-metrics to ethersphere/go-metrics

* go-metrics: add tests. move ResettingTimer logic from reporter to type.

* all, metrics: pull in metrics package in go-ethereum

* metrics/test: make sure metrics are enabled for tests

* metrics: apply gosimple rules

* metrics/exp, internal/debug: init expvar endpoint when starting pprof server

* internal/debug: tiny comment formatting fix

3 files changed, 16 insertions, 16 deletions

diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index 7ede530a9..d13247766 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -31,8 +31,8 @@ import (
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/metrics"
 	"github.com/ethereum/go-ethereum/params"
-	"github.com/rcrowley/go-metrics"
 )
 
 var (
diff --git a/eth/downloader/metrics.go b/eth/downloader/metrics.go
index 58764ccf0..d4eb33794 100644
--- a/eth/downloader/metrics.go
+++ b/eth/downloader/metrics.go
@@ -23,21 +23,21 @@ import (
 )
 
 var (
-	headerInMeter      = metrics.NewMeter("eth/downloader/headers/in")
-	headerReqTimer     = metrics.NewTimer("eth/downloader/headers/req")
-	headerDropMeter    = metrics.NewMeter("eth/downloader/headers/drop")
-	headerTimeoutMeter = metrics.NewMeter("eth/downloader/headers/timeout")
+	headerInMeter      = metrics.NewRegisteredMeter("eth/downloader/headers/in", nil)
+	headerReqTimer     = metrics.NewRegisteredTimer("eth/downloader/headers/req", nil)
+	headerDropMeter    = metrics.NewRegisteredMeter("eth/downloader/headers/drop", nil)
+	headerTimeoutMeter = metrics.NewRegisteredMeter("eth/downloader/headers/timeout", nil)
 
-	bodyInMeter      = metrics.NewMeter("eth/downloader/bodies/in")
-	bodyReqTimer     = metrics.NewTimer("eth/downloader/bodies/req")
-	bodyDropMeter    = metrics.NewMeter("eth/downloader/bodies/drop")
-	bodyTimeoutMeter = metrics.NewMeter("eth/downloader/bodies/timeout")
+	bodyInMeter      = metrics.NewRegisteredMeter("eth/downloader/bodies/in", nil)
+	bodyReqTimer     = metrics.NewRegisteredTimer("eth/downloader/bodies/req", nil)
+	bodyDropMeter    = metrics.NewRegisteredMeter("eth/downloader/bodies/drop", nil)
+	bodyTimeoutMeter = metrics.NewRegisteredMeter("eth/downloader/bodies/timeout", nil)
 
-	receiptInMeter      = metrics.NewMeter("eth/downloader/receipts/in")
-	receiptReqTimer     = metrics.NewTimer("eth/downloader/receipts/req")
-	receiptDropMeter    = metrics.NewMeter("eth/downloader/receipts/drop")
-	receiptTimeoutMeter = metrics.NewMeter("eth/downloader/receipts/timeout")
+	receiptInMeter      = metrics.NewRegisteredMeter("eth/downloader/receipts/in", nil)
+	receiptReqTimer     = metrics.NewRegisteredTimer("eth/downloader/receipts/req", nil)
+	receiptDropMeter    = metrics.NewRegisteredMeter("eth/downloader/receipts/drop", nil)
+	receiptTimeoutMeter = metrics.NewRegisteredMeter("eth/downloader/receipts/timeout", nil)
 
-	stateInMeter   = metrics.NewMeter("eth/downloader/states/in")
-	stateDropMeter = metrics.NewMeter("eth/downloader/states/drop")
+	stateInMeter   = metrics.NewRegisteredMeter("eth/downloader/states/in", nil)
+	stateDropMeter = metrics.NewRegisteredMeter("eth/downloader/states/drop", nil)
 )
diff --git a/eth/downloader/queue.go b/eth/downloader/queue.go
index a1a70e46e..359cce54b 100644
--- a/eth/downloader/queue.go
+++ b/eth/downloader/queue.go
@@ -28,7 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
-	"github.com/rcrowley/go-metrics"
+	"github.com/ethereum/go-ethereum/metrics"
 	"gopkg.in/karalabe/cookiejar.v2/collections/prque"
 )