open-nomad/vendor/github.com/prometheus/procfs/proc_io.go
2017-09-13 19:21:21 +00:00

56 lines
1.1 KiB
Go

package procfs
import (
"fmt"
"io/ioutil"
"os"
)
// ProcIO models the content of /proc/<pid>/io.
type ProcIO struct {
// Chars read.
RChar uint64
// Chars written.
WChar uint64
// Read syscalls.
SyscR uint64
// Write syscalls.
SyscW uint64
// Bytes read.
ReadBytes uint64
// Bytes written.
WriteBytes uint64
// Bytes written, but taking into account truncation. See
// Documentation/filesystems/proc.txt in the kernel sources for
// detailed explanation.
CancelledWriteBytes int64
}
// NewIO creates a new ProcIO instance from a given Proc instance.
func (p Proc) NewIO() (ProcIO, error) {
pio := ProcIO{}
f, err := os.Open(p.path("io"))
if err != nil {
return pio, err
}
defer f.Close()
data, err := ioutil.ReadAll(f)
if err != nil {
return pio, err
}
ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" +
"read_bytes: %d\nwrite_bytes: %d\n" +
"cancelled_write_bytes: %d\n"
_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
if err != nil {
return pio, err
}
return pio, nil
}