package system // import "github.com/docker/docker/pkg/system" import ( "bufio" "io" "os" "strconv" "strings" ) // ReadMemInfo retrieves memory statistics of the host system and returns a // MemInfo type. func ReadMemInfo() (*MemInfo, error) { file, err := os.Open("/proc/meminfo") if err != nil { return nil, err } defer file.Close() return parseMemInfo(file) } // parseMemInfo parses the /proc/meminfo file into // a MemInfo object given an io.Reader to the file. // Throws error if there are problems reading from the file func parseMemInfo(reader io.Reader) (*MemInfo, error) { meminfo := &MemInfo{} scanner := bufio.NewScanner(reader) memAvailable := int64(-1) for scanner.Scan() { // Expected format: ["MemTotal:", "1234", "kB"] parts := strings.Fields(scanner.Text()) // Sanity checks: Skip malformed entries. if len(parts) < 3 || parts[2] != "kB" { continue } // Convert to bytes. size, err := strconv.Atoi(parts[1]) if err != nil { continue } // Convert to KiB bytes := int64(size) * 1024 switch parts[0] { case "MemTotal:": meminfo.MemTotal = bytes case "MemFree:": meminfo.MemFree = bytes case "MemAvailable:": memAvailable = bytes case "SwapTotal:": meminfo.SwapTotal = bytes case "SwapFree:": meminfo.SwapFree = bytes } } if memAvailable != -1 { meminfo.MemFree = memAvailable } // Handle errors that may have occurred during the reading of the file. if err := scanner.Err(); err != nil { return nil, err } return meminfo, nil }