Merge pull request #1643 from giuseppe/fix-cgroupv1-usage-memory-stat

cgroups: fix memory usage on cgroup v1
containers · Sep 12, 2023 · 4eade61 · 4eade61
2 parents 890fc3f + 1a9d45c
commit 4eade61
Show file tree

Hide file tree

Showing 4 changed files with 25 additions and 6 deletions.
diff --git a/pkg/cgroups/cgroups.go b/pkg/cgroups/cgroups.go
@@ -582,7 +582,7 @@ func (c *CgroupControl) Stat() (*Metrics, error) {
 	return &m, nil
 }
 
-func readCgroup2MapPath(path string) (map[string][]string, error) {
+func readCgroupMapPath(path string) (map[string][]string, error) {
 	ret := map[string][]string{}
 	f, err := os.Open(path)
 	if err != nil {
@@ -610,5 +610,5 @@ func readCgroup2MapPath(path string) (map[string][]string, error) {
 func readCgroup2MapFile(ctr *CgroupControl, name string) (map[string][]string, error) {
 	p := filepath.Join(cgroupRoot, ctr.path, name)
 
-	return readCgroup2MapPath(p)
+	return readCgroupMapPath(p)
 }
diff --git a/pkg/cgroups/cgroups_linux.go b/pkg/cgroups/cgroups_linux.go
@@ -542,7 +542,7 @@ func (c *CgroupControl) Stat() (*cgroups.Stats, error) {
 	return &m, nil
 }
 
-func readCgroup2MapPath(path string) (map[string][]string, error) {
+func readCgroupMapPath(path string) (map[string][]string, error) {
 	ret := map[string][]string{}
 	f, err := os.Open(path)
 	if err != nil {
@@ -570,5 +570,5 @@ func readCgroup2MapPath(path string) (map[string][]string, error) {
 func readCgroup2MapFile(ctr *CgroupControl, name string) (map[string][]string, error) {
 	p := filepath.Join(cgroupRoot, ctr.config.Path, name)
 
-	return readCgroup2MapPath(p)
+	return readCgroupMapPath(p)
 }
diff --git a/pkg/cgroups/memory_linux.go b/pkg/cgroups/memory_linux.go
@@ -4,7 +4,9 @@
 package cgroups
 
 import (
+	"fmt"
 	"path/filepath"
+	"strconv"
 
 	"github.com/opencontainers/runc/libcontainer/cgroups"
 	"github.com/opencontainers/runc/libcontainer/cgroups/fs"
@@ -63,9 +65,26 @@ func (c *linuxMemHandler) Stat(ctr *CgroupControl, m *cgroups.Stats) error {
 	} else {
 		memoryRoot = ctr.getCgroupv1Path(Memory)
 		limitFilename = "memory.limit_in_bytes"
-		if memUsage.Usage.Usage, err = readFileAsUint64(filepath.Join(memoryRoot, "memory.usage_in_bytes")); err != nil {
+
+		path := filepath.Join(memoryRoot, "memory.stat")
+		values, err := readCgroupMapPath(path)
+		if err != nil {
 			return err
 		}
+
+		// cgroup v1 does not have a single "anon" field, but we can calculate it
+		// from total_active_anon and total_inactive_anon
+		memUsage.Usage.Usage = 0
+		for _, key := range []string{"total_active_anon", "total_inactive_anon"} {
+			if _, found := values[key]; !found {
+				continue
+			}
+			res, err := strconv.ParseUint(values[key][0], 10, 64)
+			if err != nil {
+				return fmt.Errorf("parse %s from %s: %w", key, path, err)
+			}
+			memUsage.Usage.Usage += res
+		}
 	}
 
 	memUsage.Usage.Limit, err = readFileAsUint64(filepath.Join(memoryRoot, limitFilename))

diff --git a/pkg/cgroups/utils.go b/pkg/cgroups/utils.go
@@ -64,7 +64,7 @@ func GetSystemCPUUsage() (uint64, error) {
 		}
 		p := filepath.Join(cgroupRoot, file.Name(), "cpu.stat")
 
-		values, err := readCgroup2MapPath(p)
+		values, err := readCgroupMapPath(p)
 		if err != nil {
 			return 0, err
 		}