Merge pull request #18630 from giuseppe/fix-mem-limit-stats

stats: get mem limit from the cgroup

libpod/stats_linux.go

@@ -5,7 +5,6 @@ package libpod
 
 import (
 	"fmt"
-	"math"
 	"strings"
 	"syscall"
 	"time"
@@ -59,7 +58,7 @@ func (c *Container) getPlatformContainerStats(stats *define.ContainerStats, prev
 	// calc the average cpu usage for the time the container is running
 	stats.AvgCPU = calculateCPUPercent(cgroupStats, 0, now, uint64(c.state.StartedTime.UnixNano()))
 	stats.MemUsage = cgroupStats.MemoryStats.Usage.Usage
-	stats.MemLimit = c.getMemLimit()
+	stats.MemLimit = c.getMemLimit(cgroupStats.MemoryStats.Usage.Limit)
 	stats.MemPerc = (float64(stats.MemUsage) / float64(stats.MemLimit)) * 100
 	stats.PIDs = 0
 	if conState == define.ContainerStateRunning || conState == define.ContainerStatePaused {
@@ -83,14 +82,7 @@ func (c *Container) getPlatformContainerStats(stats *define.ContainerStats, prev
 }
 
 // getMemory limit returns the memory limit for a container
-func (c *Container) getMemLimit() uint64 {
+func (c *Container) getMemLimit(memLimit uint64) uint64 {
-	memLimit := uint64(math.MaxUint64)
-
-	resources := c.LinuxResources()
-	if resources != nil && resources.Memory != nil && resources.Memory.Limit != nil {
-		memLimit = uint64(*resources.Memory.Limit)
-	}
-
 	si := &syscall.Sysinfo_t{}
 	err := syscall.Sysinfo(si)
 	if err != nil {

test/e2e/stats_test.go

@@ -3,6 +3,7 @@ package integration
 import (
 	"fmt"
 	"strconv"
+	"strings"
 	"time"
 
 	. "github.com/containers/podman/v4/test/utils"
@@ -181,6 +182,9 @@ var _ = Describe("Podman stats", func() {
 
 	// Regression test for #8265
 	It("podman stats with custom memory limits", func() {
+		if strings.Contains(podmanTest.OCIRuntime, "crun") {
+			Skip("Test requires crun > 1.8.4")
+		}
 		// Run three containers. One with a memory limit.  Make sure
 		// that the limits are different and the limited one has a
 		// lower limit.
@@ -229,4 +233,35 @@ var _ = Describe("Podman stats", func() {
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
 	})
+
+	It("podman stats show cgroup memory limit", func() {
+		if strings.Contains(podmanTest.OCIRuntime, "crun") {
+			Skip("Test requires crun > 1.8.4")
+		}
+		ctrWithLimit := "with-limit"
+
+		session := podmanTest.Podman([]string{"run", "-d", "--name", ctrWithLimit, "--memory", "50m", ALPINE, "top"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		session = podmanTest.Podman([]string{"stats", "--no-stream", "--format", "{{.MemLimit}}", ctrWithLimit})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		limit, err := strconv.Atoi(session.OutputToString())
+		Expect(err).ToNot(HaveOccurred())
+		Expect(limit).To(BeNumerically("==", 50*1024*1024))
+
+		session = podmanTest.Podman([]string{"container", "update", ctrWithLimit, "--memory", "100m"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		session = podmanTest.Podman([]string{"stats", "--no-stream", "--format", "{{.MemLimit}}", ctrWithLimit})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		limit, err = strconv.Atoi(session.OutputToString())
+		Expect(err).ToNot(HaveOccurred())
+		Expect(limit).To(BeNumerically("==", 100*1024*1024))
+	})
 })