all: update light logs (and a few others) to the new model

metrics/metrics.go

@@ -18,7 +18,6 @@
 package metrics
 
 import (
-	"fmt"
 	"os"
 	"runtime"
 	"strings"
@@ -41,7 +40,7 @@ var Enabled = false
 func init() {
 	for _, arg := range os.Args {
 		if strings.TrimLeft(arg, "-") == MetricsEnabledFlag {
-			log.Info(fmt.Sprintf("Enabling metrics collection"))
+			log.Info("Enabling metrics collection")
 			Enabled = true
 		}
 	}
@@ -102,7 +101,7 @@ func CollectProcessMetrics(refresh time.Duration) {
 		diskWrites = metrics.GetOrRegisterMeter("system/disk/writecount", metrics.DefaultRegistry)
 		diskWriteBytes = metrics.GetOrRegisterMeter("system/disk/writedata", metrics.DefaultRegistry)
 	} else {
-		log.Debug(fmt.Sprintf("failed to read disk metrics: %v", err))
+		log.Debug("Failed to read disk metrics", "err", err)
 	}
 	// Iterate loading the different stats and updating the meters
 	for i := 1; ; i++ {