| // +build !windows,!solaris |
| |
| package daemon |
| |
| import ( |
| "fmt" |
| "os" |
| "strconv" |
| "strings" |
| |
| sysinfo "github.com/docker/docker/pkg/system" |
| "github.com/opencontainers/runc/libcontainer/system" |
| ) |
| |
| // platformNewStatsCollector performs platform specific initialisation of the |
| // statsCollector structure. |
| func platformNewStatsCollector(s *statsCollector) { |
| s.clockTicksPerSecond = uint64(system.GetClockTicks()) |
| meminfo, err := sysinfo.ReadMemInfo() |
| if err == nil && meminfo.MemTotal > 0 { |
| s.machineMemory = uint64(meminfo.MemTotal) |
| } |
| } |
| |
| const nanoSecondsPerSecond = 1e9 |
| |
| // getSystemCPUUsage returns the host system's cpu usage in |
| // nanoseconds. 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 (s *statsCollector) getSystemCPUUsage() (uint64, error) { |
| var line string |
| f, err := os.Open("/proc/stat") |
| if err != nil { |
| return 0, err |
| } |
| defer func() { |
| s.bufReader.Reset(nil) |
| f.Close() |
| }() |
| s.bufReader.Reset(f) |
| err = nil |
| for err == nil { |
| line, err = s.bufReader.ReadString('\n') |
| if err != nil { |
| break |
| } |
| parts := strings.Fields(line) |
| switch parts[0] { |
| case "cpu": |
| if len(parts) < 8 { |
| return 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, fmt.Errorf("Unable to convert value %s to int: %s", i, err) |
| } |
| totalClockTicks += v |
| } |
| return (totalClockTicks * nanoSecondsPerSecond) / |
| s.clockTicksPerSecond, nil |
| } |
| } |
| return 0, fmt.Errorf("invalid stat format. Error trying to parse the '/proc/stat' file") |
| } |