Add diskio stats to cAdvisor.

Docker-DCO-1.1-Signed-off-by: Rohit Jnagal <jnagal@google.com> (github: rjnagal)

container/libcontainer/helpers.go

@@ -15,6 +15,7 @@
 package libcontainer
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/docker/libcontainer"
@@ -41,6 +42,40 @@ func GetStatsCgroupOnly(cgroup *cgroups.Cgroup) (*info.ContainerStats, error) {
 	return toContainerStats(&libcontainer.ContainerStats{CgroupStats: s}), nil
 }
 
+func DiskStatsCopy(blkio_stats []cgroups.BlkioStatEntry) (stat []info.PerDiskStats) {
+	if len(blkio_stats) == 0 {
+		return
+	}
+	disk_stat := make(map[string]*info.PerDiskStats)
+	for i := range blkio_stats {
+		major := blkio_stats[i].Major
+		minor := blkio_stats[i].Minor
+		device_string := fmt.Sprintf("%d:%d", major, minor)
+		diskp, ok := disk_stat[device_string]
+		if !ok {
+			disk := info.PerDiskStats{
+				Major: major,
+				Minor: minor,
+			}
+			disk.Stats = make(map[string]uint64)
+			diskp = &disk
+			disk_stat[device_string] = diskp
+		}
+		op := blkio_stats[i].Op
+		if op == "" {
+			op = "Count"
+		}
+		diskp.Stats[op] = blkio_stats[i].Value
+	}
+	i := 0
+	stat = make([]info.PerDiskStats, len(disk_stat))
+	for _, disk := range disk_stat {
+		stat[i] = *disk
+		i++
+	}
+	return
+}
+
 // Convert libcontainer stats to info.ContainerStats.
 func toContainerStats(libcontainerStats *libcontainer.ContainerStats) *info.ContainerStats {
 	s := libcontainerStats.CgroupStats
@@ -59,6 +94,13 @@ func toContainerStats(libcontainerStats *libcontainer.ContainerStats) *info.Cont
 			ret.Cpu.Usage.PerCpu[i] = s.CpuStats.CpuUsage.PercpuUsage[i]
 			ret.Cpu.Usage.Total += s.CpuStats.CpuUsage.PercpuUsage[i]
 		}
+
+		ret.DiskIo = new(info.DiskIoStats)
+		ret.DiskIo.IoServiceBytes = DiskStatsCopy(s.BlkioStats.IoServiceBytesRecursive)
+		ret.DiskIo.IoServiced = DiskStatsCopy(s.BlkioStats.IoServicedRecursive)
+		ret.DiskIo.IoQueued = DiskStatsCopy(s.BlkioStats.IoQueuedRecursive)
+		ret.DiskIo.Sectors = DiskStatsCopy(s.BlkioStats.SectorsRecursive)
+
 		ret.Memory = new(info.MemoryStats)
 		ret.Memory.Usage = s.MemoryStats.Usage
 		if v, ok := s.MemoryStats.Stats["pgfault"]; ok {

info/container.go

@@ -166,6 +166,19 @@ type CpuStats struct {
 	Load int32 `json:"load"`
 }
 
+type PerDiskStats struct {
+	Major uint64            `json:"major"`
+	Minor uint64            `json:"minor"`
+	Stats map[string]uint64 `json:"stats"`
+}
+
+type DiskIoStats struct {
+	IoServiceBytes []PerDiskStats `json:"io_service_bytes,omitempty"`
+	IoServiced     []PerDiskStats `json:"io_serviced,omitempty"`
+	IoQueued       []PerDiskStats `json:"io_queued,omitempty"`
+	Sectors        []PerDiskStats `json"sectors,omitempty"`
+}
+
 type MemoryStats struct {
 	// Memory limit, equivalent to "limit" in MemorySpec.
 	// Units: Bytes.
@@ -215,6 +228,7 @@ type ContainerStats struct {
 	// The time of this stat point.
 	Timestamp time.Time     `json:"timestamp"`
 	Cpu       *CpuStats     `json:"cpu,omitempty"`
+	DiskIo    *DiskIoStats  `json:"diskio,omitempty"`
 	Memory    *MemoryStats  `json:"memory,omitempty"`
 	Network   *NetworkStats `json:"network,omitempty"`
 }