node_exporter/collector/filesystem_linux.go
Brian Brazil 7e41a2b279 Ignore /var/lib/docker by default. (#814)
The node exporter runs unprivileged, so it cannot statfs any filesystems
under this directory causing log spam.  In addition there tends to be
high churn in the filesystems here (as it's basically application
monitoring) which can cause high cardinaltiy and in one case caused
Prometheus's index symbol table to get very large.
Accordingly this should be ignored to reduce log spam and avoid
performance issues. The filesystems themselves can in principle be
monitored via container oriented exporters, and the underlying
filesystems will still be monitored.
2018-02-06 17:10:59 +01:00

98 lines
2.6 KiB
Go

// 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 !nofilesystem
package collector
import (
"bufio"
"os"
"strings"
"syscall"
"github.com/prometheus/common/log"
)
const (
defIgnoredMountPoints = "^/(dev|proc|sys|var/lib/docker)($|/)"
defIgnoredFSTypes = "^(autofs|binfmt_misc|cgroup|configfs|debugfs|devpts|devtmpfs|fusectl|hugetlbfs|mqueue|proc|procfs|pstore|rpc_pipefs|securityfs|sysfs|tracefs)$"
readOnly = 0x1 // ST_RDONLY
)
// GetStats returns filesystem stats.
func (c *filesystemCollector) GetStats() ([]filesystemStats, error) {
mps, err := mountPointDetails()
if err != nil {
return nil, err
}
stats := []filesystemStats{}
for _, labels := range mps {
if c.ignoredMountPointsPattern.MatchString(labels.mountPoint) {
log.Debugf("Ignoring mount point: %s", labels.mountPoint)
continue
}
if c.ignoredFSTypesPattern.MatchString(labels.fsType) {
log.Debugf("Ignoring fs type: %s", labels.fsType)
continue
}
buf := new(syscall.Statfs_t)
err := syscall.Statfs(labels.mountPoint, buf)
if err != nil {
stats = append(stats, filesystemStats{
labels: labels,
deviceError: 1,
})
log.Errorf("Error on statfs() system call for %q: %s", labels.mountPoint, err)
continue
}
var ro float64
if (buf.Flags & readOnly) != 0 {
ro = 1
}
stats = append(stats, filesystemStats{
labels: labels,
size: float64(buf.Blocks) * float64(buf.Bsize),
free: float64(buf.Bfree) * float64(buf.Bsize),
avail: float64(buf.Bavail) * float64(buf.Bsize),
files: float64(buf.Files),
filesFree: float64(buf.Ffree),
ro: ro,
})
}
return stats, nil
}
func mountPointDetails() ([]filesystemLabels, error) {
file, err := os.Open(procFilePath("mounts"))
if err != nil {
return nil, err
}
defer file.Close()
filesystems := []filesystemLabels{}
scanner := bufio.NewScanner(file)
for scanner.Scan() {
parts := strings.Fields(scanner.Text())
filesystems = append(filesystems, filesystemLabels{
device: parts[0],
mountPoint: parts[1],
fsType: parts[2],
})
}
return filesystems, scanner.Err()
}