Add streaming stats to bolt bench.

This commit adds -stats-interval to the 'bolt bench' utility. By setting this argument
to an interval greater than 0s, the benchmark tool will output stats as streaming JSON.
This data can, in turn, be graphed to understand performance over time.

1 files changed, 18 insertions, 10 deletions

diff --git a/cmd/bolt/main.go b/cmd/bolt/main.go
index cb2d47a..3558500 100644
--- a/cmd/bolt/main.go
+++ b/cmd/bolt/main.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"time"
 
 	"github.com/codegangsta/cli"
 )
@@ -104,19 +105,26 @@ func NewApp() *cli.App {
 				&cli.StringFlag{Name: "cpuprofile", Usage: "CPU profile output path"},
 				&cli.StringFlag{Name: "memprofile", Usage: "Memory profile output path"},
 				&cli.StringFlag{Name: "blockprofile", Usage: "Block profile output path"},
+				&cli.StringFlag{Name: "stats-interval", Value: "0s", Usage: "Continuous stats interval"},
 			},
 			Action: func(c *cli.Context) {
+				statsInterval, err := time.ParseDuration(c.String("stats-interval"))
+				if err != nil {
+					fatal(err)
+				}
+
 				Bench(&BenchOptions{
-					ProfileMode:  c.String("profile-mode"),
-					WriteMode:    c.String("write-mode"),
-					ReadMode:     c.String("read-mode"),
-					Iterations:   c.Int("count"),
-					BatchSize:    c.Int("batch-size"),
-					KeySize:      c.Int("key-size"),
-					ValueSize:    c.Int("value-size"),
-					CPUProfile:   c.String("cpuprofile"),
-					MemProfile:   c.String("memprofile"),
-					BlockProfile: c.String("blockprofile"),
+					ProfileMode:   c.String("profile-mode"),
+					WriteMode:     c.String("write-mode"),
+					ReadMode:      c.String("read-mode"),
+					Iterations:    c.Int("count"),
+					BatchSize:     c.Int("batch-size"),
+					KeySize:       c.Int("key-size"),
+					ValueSize:     c.Int("value-size"),
+					CPUProfile:    c.String("cpuprofile"),
+					MemProfile:    c.String("memprofile"),
+					BlockProfile:  c.String("blockprofile"),
+					StatsInterval: statsInterval,
 				})
 			},
 		}}