Include system RAM size in usage report

cmd/syncthing/memsize_darwin.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"errors"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+func memorySize() (uint64, error) {
+	cmd := exec.Command("sysctl", "hw.memsize")
+	out, err := cmd.Output()
+	if err != nil {
+		return 0, err
+	}
+	fs := strings.Fields(string(out))
+	if len(fs) != 2 {
+		return 0, errors.New("sysctl parse error")
+	}
+	bytes, err := strconv.ParseUint(fs[1], 10, 64)
+	if err != nil {
+		return 0, err
+	}
+	return bytes, nil
+}

cmd/syncthing/memsize_linux.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"bufio"
+	"errors"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func memorySize() (uint64, error) {
+	f, err := os.Open("/proc/meminfo")
+	if err != nil {
+		return 0, err
+	}
+
+	s := bufio.NewScanner(f)
+	if !s.Scan() {
+		return 0, errors.New("/proc/meminfo parse error 1")
+	}
+
+	l := s.Text()
+	fs := strings.Fields(l)
+	if len(fs) != 3 || fs[2] != "kB" {
+		return 0, errors.New("/proc/meminfo parse error 2")
+	}
+
+	kb, err := strconv.ParseUint(fs[1], 10, 64)
+	if err != nil {
+		return 0, err
+	}
+	return kb * 1024, nil
+}

cmd/syncthing/memsize_unimpl.go

@@ -0,0 +1,9 @@
+// +build freebsd solaris
+
+package main
+
+import "errors"
+
+func memorySize() (uint64, error) {
+	return 0, errors.New("not implemented")
+}

cmd/syncthing/memsize_windows.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"encoding/binary"
+	"syscall"
+	"unsafe"
+)
+
+var (
+	kernel32, _             = syscall.LoadLibrary("kernel32.dll")
+	globalMemoryStatusEx, _ = syscall.GetProcAddress(kernel32, "GlobalMemoryStatusEx")
+)
+
+func memorySize() (uint64, error) {
+	var memoryStatusEx [64]byte
+	binary.LittleEndian.PutUint32(memoryStatusEx[:], 64)
+	p := uintptr(unsafe.Pointer(&memoryStatusEx[0]))
+
+	ret, _, callErr := syscall.Syscall(uintptr(globalMemoryStatusEx), 1, p, 0, 0)
+	if ret == 0 {
+		return 0, callErr
+	}
+
+	return binary.LittleEndian.Uint64(memoryStatusEx[8:]), nil
+}

cmd/syncthing/usage_report.go

@@ -61,6 +61,11 @@ func reportData(m *model.Model) map[string]interface{} {
 	}
 	res["sha256Perf"] = perf
 
+	bytes, err := memorySize()
+	if err == nil {
+		res["memorySize"] = bytes / 1024 / 1024
+	}
+
 	return res
 }