Add meminfo stats for Darwin

collector/meminfo.go

@@ -32,8 +32,7 @@ func init() {
 	Factories["meminfo"] = NewMeminfoCollector
 }
 
-// Takes a prometheus registry and returns a new Collector exposing
+// NewMeminfoCollector returns a new Collector exposing memory stats.
-// memory stats.
 func NewMeminfoCollector() (Collector, error) {
 	return &meminfoCollector{}, nil
 }

collector/meminfo_bsd.go

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build darwin freebsd dragonfly
+// +build freebsd dragonfly
 // +build !nomeminfo
 
 package collector

collector/meminfo_darwin.go

@@ -0,0 +1,59 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !nomeminfo
+
+package collector
+
+// #include <mach/mach_host.h>
+import "C"
+
+import (
+	"encoding/binary"
+	"fmt"
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+func (c *meminfoCollector) getMemInfo() (map[string]float64, error) {
+	infoCount := C.mach_msg_type_number_t(C.HOST_VM_INFO_COUNT)
+	vmstat := C.vm_statistics_data_t{}
+	ret := C.host_statistics(
+		C.host_t(C.mach_host_self()),
+		C.HOST_VM_INFO,
+		C.host_info_t(unsafe.Pointer(&vmstat)),
+		&infoCount,
+	)
+	if ret != C.KERN_SUCCESS {
+		return nil, fmt.Errorf("Couldn't get memory statistics, host_statistics returned %d", ret)
+	}
+	totalb, err := unix.Sysctl("hw.memsize")
+	if err != nil {
+		return nil, err
+	}
+	// Syscall removes terminating NUL which we need to cast to uint64
+	total := binary.LittleEndian.Uint64([]byte(totalb + "\x00"))
+
+	ps := C.natural_t(syscall.Getpagesize())
+	return map[string]float64{
+		"active_bytes_total":      float64(ps * vmstat.active_count),
+		"inactive_bytes_total":    float64(ps * vmstat.inactive_count),
+		"wired_bytes_total":       float64(ps * vmstat.wire_count),
+		"free_bytes_total":        float64(ps * vmstat.free_count),
+		"swapped_in_pages_total":  float64(ps * vmstat.pageins),
+		"swapped_out_pages_total": float64(ps * vmstat.pageouts),
+		"bytes_total":             float64(total),
+	}, nil
+}