Make IOPerDrive Configurable

Signed-off-by: Zhou Ting <ting.z.zhou@intel.com>

README.md

@@ -50,6 +50,7 @@ Examples:
 Flags:
   -b, --blocksize string   read/write block size (default "4MiB")
   -f, --filesize string    amount of data to read/write per drive (default "1GiB")
+  -i, --ioperdrive int     number of concurrent I/O per drive (default 4)
   -h, --help               help for dperf
       --serial             run tests one by one, instead of all at once.
       --version            version for dperf

cmd/cmd.go

@@ -42,11 +42,12 @@ const alignSize = 4096
 
 // flags
 var (
-	serial    = false
-	verbose   = false
-	blockSize = "4MiB"
-	fileSize  = "1GiB"
-	cpuNode   = 0
+	serial     = false
+	verbose    = false
+	blockSize  = "4MiB"
+	fileSize   = "1GiB"
+	cpuNode    = 0
+	ioPerDrive = 4
 )
 
 var dperfCmd = &cobra.Command{
@@ -123,11 +124,16 @@ $ dperf --serial /mnt/drive{1..6}
 			return fmt.Errorf("Invalid filesize must multiples of 4k: %d", fs)
 		}
 
+		if ioPerDrive <= 0 {
+			return fmt.Errorf("Invalid ioperdrive must greater than 0: %d", ioPerDrive)
+		}
+
 		perf := &dperf.DrivePerf{
-			Serial:    serial,
-			BlockSize: bs,
-			FileSize:  fs,
-			Verbose:   verbose,
+			Serial:     serial,
+			BlockSize:  bs,
+			FileSize:   fs,
+			Verbose:    verbose,
+			IOPerDrive: ioPerDrive,
 		}
 		paths := make([]string, 0, len(args))
 		for _, arg := range args {
@@ -175,6 +181,8 @@ func init() {
 		"filesize", "f", fileSize, "amount of data to read/write per drive")
 	dperfCmd.PersistentFlags().IntVarP(&cpuNode,
 		"cpunode", "c", -1, "execute on a specific CPU node, defaults to all CPU nodes")
+	dperfCmd.PersistentFlags().IntVarP(&ioPerDrive,
+		"ioperdrive", "i", ioPerDrive, "number of concurrent I/O per drive, default is 4")
 
 	dperfCmd.PersistentFlags().MarkHidden("alsologtostderr")
 	dperfCmd.PersistentFlags().MarkHidden("add_dir_header")

pkg/dperf/perf.go

@@ -30,10 +30,11 @@ import (
 
 // DrivePerf options
 type DrivePerf struct {
-	Serial    bool
-	Verbose   bool
-	BlockSize uint64
-	FileSize  uint64
+	Serial     bool
+	Verbose    bool
+	BlockSize  uint64
+	FileSize   uint64
+	IOPerDrive int
 }
 
 // mustGetUUID - get a random UUID.
@@ -46,15 +47,13 @@ func mustGetUUID() string {
 	return u.String()
 }
 
-const ioPerDrive = 4 // number of concurrent I/O per drive
-
 func (d *DrivePerf) runTests(ctx context.Context, path string, testUUID string) (dr *DrivePerfResult) {
-	writeThroughputs := make([]uint64, ioPerDrive)
-	readThroughputs := make([]uint64, ioPerDrive)
-	errs := make([]error, ioPerDrive)
+	writeThroughputs := make([]uint64, d.IOPerDrive)
+	readThroughputs := make([]uint64, d.IOPerDrive)
+	errs := make([]error, d.IOPerDrive)
 
-	dataBuffers := make([][]byte, ioPerDrive)
-	for i := 0; i < ioPerDrive; i++ {
+	dataBuffers := make([][]byte, d.IOPerDrive)
+	for i := 0; i < d.IOPerDrive; i++ {
 		// Read Aligned block upto a multiple of BlockSize
 		dataBuffers[i] = directio.AlignedBlock(int(d.BlockSize))
 	}
@@ -64,8 +63,8 @@ func (d *DrivePerf) runTests(ctx context.Context, path string, testUUID string)
 	defer os.RemoveAll(testUUIDPath)
 
 	var wg sync.WaitGroup
-	wg.Add(ioPerDrive)
-	for i := 0; i < ioPerDrive; i++ {
+	wg.Add(int(d.IOPerDrive))
+	for i := 0; i < int(d.IOPerDrive); i++ {
 		go func(idx int) {
 			defer wg.Done()
 			iopath := testPath + "-" + strconv.Itoa(idx)
@@ -79,8 +78,8 @@ func (d *DrivePerf) runTests(ctx context.Context, path string, testUUID string)
 	}
 	wg.Wait()
 
-	wg.Add(ioPerDrive)
-	for i := 0; i < ioPerDrive; i++ {
+	wg.Add(d.IOPerDrive)
+	for i := 0; i < d.IOPerDrive; i++ {
 		go func(idx int) {
 			defer wg.Done()
 			iopath := testPath + "-" + strconv.Itoa(idx)