dotcloud/docker

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daemon/stats_unix.go

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//go:build !windows

package daemon // import "github.com/docker/docker/daemon"

import (
    "bufio"
    "context"
    "fmt"
    "os"
    "strconv"
    "strings"

    statsV1 "github.com/containerd/cgroups/v3/cgroup1/stats"
    statsV2 "github.com/containerd/cgroups/v3/cgroup2/stats"
    containertypes "github.com/docker/docker/api/types/container"
    "github.com/docker/docker/container"
    "github.com/pkg/errors"
)

func copyBlkioEntry(entries []*statsV1.BlkIOEntry) []containertypes.BlkioStatEntry {
    out := make([]containertypes.BlkioStatEntry, len(entries))
    for i, re := range entries {
        out[i] = containertypes.BlkioStatEntry{
            Major: re.Major,
            Minor: re.Minor,
            Op:    re.Op,
            Value: re.Value,
        }
    }
    return out
}

func (daemon *Daemon) stats(c *container.Container) (*containertypes.StatsResponse, error) {
    c.Lock()
    task, err := c.GetRunningTask()
    c.Unlock()
    if err != nil {
        return nil, err
    }
    cs, err := task.Stats(context.Background())
    if err != nil {
        if strings.Contains(err.Error(), "container not found") {
            return nil, containerNotFound(c.ID)
        }
        return nil, err
    }
    s := &containertypes.StatsResponse{}
    s.Read = cs.Read
    stats := cs.Metrics
    switch t := stats.(type) {
    case *statsV1.Metrics:
        return daemon.statsV1(s, t)
    case *statsV2.Metrics:
        return daemon.statsV2(s, t)
    default:
        return nil, errors.Errorf("unexpected type of metrics %+v", t)
    }
}

func (daemon *Daemon) statsV1(s *containertypes.StatsResponse, stats *statsV1.Metrics) (*containertypes.StatsResponse, error) {
    if stats.Blkio != nil {
        s.BlkioStats = containertypes.BlkioStats{
            IoServiceBytesRecursive: copyBlkioEntry(stats.Blkio.IoServiceBytesRecursive),
            IoServicedRecursive:     copyBlkioEntry(stats.Blkio.IoServicedRecursive),
            IoQueuedRecursive:       copyBlkioEntry(stats.Blkio.IoQueuedRecursive),
            IoServiceTimeRecursive:  copyBlkioEntry(stats.Blkio.IoServiceTimeRecursive),
            IoWaitTimeRecursive:     copyBlkioEntry(stats.Blkio.IoWaitTimeRecursive),
            IoMergedRecursive:       copyBlkioEntry(stats.Blkio.IoMergedRecursive),
            IoTimeRecursive:         copyBlkioEntry(stats.Blkio.IoTimeRecursive),
            SectorsRecursive:        copyBlkioEntry(stats.Blkio.SectorsRecursive),
        }
    }
    if stats.CPU != nil {
        s.CPUStats = containertypes.CPUStats{
            CPUUsage: containertypes.CPUUsage{
                TotalUsage:        stats.CPU.Usage.Total,
                PercpuUsage:       stats.CPU.Usage.PerCPU,
                UsageInKernelmode: stats.CPU.Usage.Kernel,
                UsageInUsermode:   stats.CPU.Usage.User,
            },
            ThrottlingData: containertypes.ThrottlingData{
                Periods:          stats.CPU.Throttling.Periods,
                ThrottledPeriods: stats.CPU.Throttling.ThrottledPeriods,
                ThrottledTime:    stats.CPU.Throttling.ThrottledTime,
            },
        }
    }

    if stats.Memory != nil {
        raw := map[string]uint64{
            "cache":                     stats.Memory.Cache,
            "rss":                       stats.Memory.RSS,
            "rss_huge":                  stats.Memory.RSSHuge,
            "mapped_file":               stats.Memory.MappedFile,
            "dirty":                     stats.Memory.Dirty,
            "writeback":                 stats.Memory.Writeback,
            "pgpgin":                    stats.Memory.PgPgIn,
            "pgpgout":                   stats.Memory.PgPgOut,
            "pgfault":                   stats.Memory.PgFault,
            "pgmajfault":                stats.Memory.PgMajFault,
            "inactive_anon":             stats.Memory.InactiveAnon,
            "active_anon":               stats.Memory.ActiveAnon,
            "inactive_file":             stats.Memory.InactiveFile,
            "active_file":               stats.Memory.ActiveFile,
            "unevictable":               stats.Memory.Unevictable,
            "hierarchical_memory_limit": stats.Memory.HierarchicalMemoryLimit,
            "hierarchical_memsw_limit":  stats.Memory.HierarchicalSwapLimit,
            "total_cache":               stats.Memory.TotalCache,
            "total_rss":                 stats.Memory.TotalRSS,
            "total_rss_huge":            stats.Memory.TotalRSSHuge,
            "total_mapped_file":         stats.Memory.TotalMappedFile,
            "total_dirty":               stats.Memory.TotalDirty,
            "total_writeback":           stats.Memory.TotalWriteback,
            "total_pgpgin":              stats.Memory.TotalPgPgIn,
            "total_pgpgout":             stats.Memory.TotalPgPgOut,
            "total_pgfault":             stats.Memory.TotalPgFault,
            "total_pgmajfault":          stats.Memory.TotalPgMajFault,
            "total_inactive_anon":       stats.Memory.TotalInactiveAnon,
            "total_active_anon":         stats.Memory.TotalActiveAnon,
            "total_inactive_file":       stats.Memory.TotalInactiveFile,
            "total_active_file":         stats.Memory.TotalActiveFile,
            "total_unevictable":         stats.Memory.TotalUnevictable,
        }
        if stats.Memory.Usage != nil {
            s.MemoryStats = containertypes.MemoryStats{
                Stats:    raw,
                Usage:    stats.Memory.Usage.Usage,
                MaxUsage: stats.Memory.Usage.Max,
                Limit:    stats.Memory.Usage.Limit,
                Failcnt:  stats.Memory.Usage.Failcnt,
            }
        } else {
            s.MemoryStats = containertypes.MemoryStats{
                Stats: raw,
            }
        }

        // if the container does not set memory limit, use the machineMemory
        if s.MemoryStats.Limit > daemon.machineMemory && daemon.machineMemory > 0 {
            s.MemoryStats.Limit = daemon.machineMemory
        }
    }

    if stats.Pids != nil {
        s.PidsStats = containertypes.PidsStats{
            Current: stats.Pids.Current,
            Limit:   stats.Pids.Limit,
        }
    }

    return s, nil
}

func (daemon *Daemon) statsV2(s *containertypes.StatsResponse, stats *statsV2.Metrics) (*containertypes.StatsResponse, error) {
    if stats.Io != nil {
        var isbr []containertypes.BlkioStatEntry
        for _, re := range stats.Io.Usage {
            isbr = append(isbr,
                containertypes.BlkioStatEntry{
                    Major: re.Major,
                    Minor: re.Minor,
                    Op:    "read",
                    Value: re.Rbytes,
                },
                containertypes.BlkioStatEntry{
                    Major: re.Major,
                    Minor: re.Minor,
                    Op:    "write",
                    Value: re.Wbytes,
                },
            )
        }
        s.BlkioStats = containertypes.BlkioStats{
            IoServiceBytesRecursive: isbr,
            // Other fields are unsupported
        }
    }

    if stats.CPU != nil {
        s.CPUStats = containertypes.CPUStats{
            CPUUsage: containertypes.CPUUsage{
                TotalUsage: stats.CPU.UsageUsec * 1000,
                // PercpuUsage is not supported
                UsageInKernelmode: stats.CPU.SystemUsec * 1000,
                UsageInUsermode:   stats.CPU.UserUsec * 1000,
            },
            ThrottlingData: containertypes.ThrottlingData{
                Periods:          stats.CPU.NrPeriods,
                ThrottledPeriods: stats.CPU.NrThrottled,
                ThrottledTime:    stats.CPU.ThrottledUsec * 1000,
            },
        }
    }

    if stats.Memory != nil {
        s.MemoryStats = containertypes.MemoryStats{
            // Stats is not compatible with v1
            Stats: map[string]uint64{
                "anon":                   stats.Memory.Anon,
                "file":                   stats.Memory.File,
                "kernel_stack":           stats.Memory.KernelStack,
                "slab":                   stats.Memory.Slab,
                "sock":                   stats.Memory.Sock,
                "shmem":                  stats.Memory.Shmem,
                "file_mapped":            stats.Memory.FileMapped,
                "file_dirty":             stats.Memory.FileDirty,
                "file_writeback":         stats.Memory.FileWriteback,
                "anon_thp":               stats.Memory.AnonThp,
                "inactive_anon":          stats.Memory.InactiveAnon,
                "active_anon":            stats.Memory.ActiveAnon,
                "inactive_file":          stats.Memory.InactiveFile,
                "active_file":            stats.Memory.ActiveFile,
                "unevictable":            stats.Memory.Unevictable,
                "slab_reclaimable":       stats.Memory.SlabReclaimable,
                "slab_unreclaimable":     stats.Memory.SlabUnreclaimable,
                "pgfault":                stats.Memory.Pgfault,
                "pgmajfault":             stats.Memory.Pgmajfault,
                "workingset_refault":     stats.Memory.WorkingsetRefault,
                "workingset_activate":    stats.Memory.WorkingsetActivate,
                "workingset_nodereclaim": stats.Memory.WorkingsetNodereclaim,
                "pgrefill":               stats.Memory.Pgrefill,
                "pgscan":                 stats.Memory.Pgscan,
                "pgsteal":                stats.Memory.Pgsteal,
                "pgactivate":             stats.Memory.Pgactivate,
                "pgdeactivate":           stats.Memory.Pgdeactivate,
                "pglazyfree":             stats.Memory.Pglazyfree,
                "pglazyfreed":            stats.Memory.Pglazyfreed,
                "thp_fault_alloc":        stats.Memory.ThpFaultAlloc,
                "thp_collapse_alloc":     stats.Memory.ThpCollapseAlloc,
            },
            Usage: stats.Memory.Usage,
            // MaxUsage is not supported
            Limit: stats.Memory.UsageLimit,
        }
        // if the container does not set memory limit, use the machineMemory
        if s.MemoryStats.Limit > daemon.machineMemory && daemon.machineMemory > 0 {
            s.MemoryStats.Limit = daemon.machineMemory
        }
        if stats.MemoryEvents != nil {
            // Failcnt is set to the "oom" field of the "memory.events" file.
            // See https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.html
            s.MemoryStats.Failcnt = stats.MemoryEvents.Oom
        }
    }

    if stats.Pids != nil {
        s.PidsStats = containertypes.PidsStats{
            Current: stats.Pids.Current,
            Limit:   stats.Pids.Limit,
        }
    }

    return s, nil
}

// Resolve Network SandboxID in case the container reuse another container's network stack
func (daemon *Daemon) getNetworkSandboxID(c *container.Container) (string, error) {
    curr := c
    for curr.HostConfig.NetworkMode.IsContainer() {
        containerID := curr.HostConfig.NetworkMode.ConnectedContainer()
        connected, err := daemon.GetContainer(containerID)
        if err != nil {
            return "", errors.Wrapf(err, "Could not get container for %s", containerID)
        }
        curr = connected
    }
    return curr.NetworkSettings.SandboxID, nil
}

func (daemon *Daemon) getNetworkStats(c *container.Container) (map[string]containertypes.NetworkStats, error) {
    sandboxID, err := daemon.getNetworkSandboxID(c)
    if err != nil {
        return nil, err
    }

    sb, err := daemon.netController.SandboxByID(sandboxID)
    if err != nil {
        return nil, err
    }

    lnstats, err := sb.Statistics()
    if err != nil {
        return nil, err
    }

    stats := make(map[string]containertypes.NetworkStats)
    // Convert libnetwork nw stats into api stats
    for ifName, ifStats := range lnstats {
        stats[ifName] = containertypes.NetworkStats{
            RxBytes:   ifStats.RxBytes,
            RxPackets: ifStats.RxPackets,
            RxErrors:  ifStats.RxErrors,
            RxDropped: ifStats.RxDropped,
            TxBytes:   ifStats.TxBytes,
            TxPackets: ifStats.TxPackets,
            TxErrors:  ifStats.TxErrors,
            TxDropped: ifStats.TxDropped,
        }
    }

    return stats, nil
}

const (
    // The value comes from `C.sysconf(C._SC_CLK_TCK)`, and
    // on Linux it's a constant which is safe to be hard coded,
    // so we can avoid using cgo here. For details, see:
    // https://github.com/containerd/cgroups/pull/12
    clockTicksPerSecond  = 100
    nanoSecondsPerSecond = 1e9
)

// getSystemCPUUsage returns the host system's cpu usage in
// nanoseconds and number of online CPUs. An error is returned
// if the format of the underlying file does not match.
//
// Uses /proc/stat defined by POSIX. Looks for the cpu
// statistics line and then sums up the first seven fields
// provided. See `man 5 proc` for details on specific field
// information.
func getSystemCPUUsage() (cpuUsage uint64, cpuNum uint32, err error) {
    f, err := os.Open("/proc/stat")
    if err != nil {
        return 0, 0, err
    }
    defer f.Close()

    scanner := bufio.NewScanner(f)
    for scanner.Scan() {
        line := scanner.Text()
        if len(line) < 4 || line[:3] != "cpu" {
            break // Assume all cpu* records are at the front, like glibc https://github.com/bminor/glibc/blob/5d00c201b9a2da768a79ea8d5311f257871c0b43/sysdeps/unix/sysv/linux/getsysstats.c#L108-L135
        }
        if line[3] == ' ' {
            parts := strings.Fields(line)
            if len(parts) < 8 {
                return 0, 0, fmt.Errorf("invalid number of cpu fields")
            }
            var totalClockTicks uint64
            for _, i := range parts[1:8] {
                v, err := strconv.ParseUint(i, 10, 64)
                if err != nil {
                    return 0, 0, fmt.Errorf("Unable to convert value %s to int: %w", i, err)
                }
                totalClockTicks += v
            }
            cpuUsage = (totalClockTicks * nanoSecondsPerSecond) /
                clockTicksPerSecond
        }
        if '0' <= line[3] && line[3] <= '9' {
            cpuNum++
        }
    }

    if err := scanner.Err(); err != nil {
        return 0, 0, fmt.Errorf("error scanning '/proc/stat' file: %w", err)
    }
    return
}