1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
// Copyright 2020 New Relic Corporation. All rights reserved.
// SPDX-License-Identifier: Apache-2.0
package sysinfo
import (
"errors"
"os/exec"
"regexp"
"strconv"
"strings"
"testing"
)
func TestPhysicalMemoryBytes(t *testing.T) {
prtconf, err := prtconfMemoryBytes()
if err != nil {
t.Fatal(err)
}
sysconf, err := PhysicalMemoryBytes()
if err != nil {
t.Fatal(err)
}
// The pagesize*pages calculation, although standard (the JVM, at least,
// uses this approach), doesn't match up exactly with the number
// returned by prtconf.
if sysconf > prtconf || sysconf < (prtconf-prtconf/20) {
t.Fatal(prtconf, sysconf)
}
}
var (
ptrconfRe = regexp.MustCompile(`[Mm]emory\s*size:\s*([0-9]+)\s*([a-zA-Z]+)`)
)
func prtconfMemoryBytes() (uint64, error) {
output, err := exec.Command("/usr/sbin/prtconf").Output()
if err != nil {
return 0, err
}
m := ptrconfRe.FindSubmatch(output)
if m == nil {
return 0, errors.New("memory size not found in prtconf output")
}
size, err := strconv.ParseUint(string(m[1]), 10, 64)
if err != nil {
return 0, err
}
switch strings.ToLower(string(m[2])) {
case "megabytes", "mb":
return size * 1024 * 1024, nil
case "kilobytes", "kb":
return size * 1024, nil
default:
return 0, errors.New("couldn't parse memory size in prtconf output")
}
}
|
