6 files changed, 106 insertions, 25 deletions
diff --git a/libpod/container_api.go b/libpod/container_api.go
index 38223316e..b0ea7c0de 100644
--- a/libpod/container_api.go
+++ b/libpod/container_api.go
@@ -794,21 +794,29 @@ type ContainerCheckpointOptions struct {
 	// container no PID 1 will be in the namespace and that is not
 	// possible.
 	Pod string
+	// PrintStats tells the API to fill out the statistics about
+	// how much time each component in the stack requires to
+	// checkpoint a container.
+	PrintStats bool
 }
 
 // Checkpoint checkpoints a container
-func (c *Container) Checkpoint(ctx context.Context, options ContainerCheckpointOptions) error {
+// The return values *define.CRIUCheckpointRestoreStatistics and int64 (time
+// the runtime needs to checkpoint the container) are only set if
+// options.PrintStats is set to true. Not setting options.PrintStats to true
+// will return nil and 0.
+func (c *Container) Checkpoint(ctx context.Context, options ContainerCheckpointOptions) (*define.CRIUCheckpointRestoreStatistics, int64, error) {
 	logrus.Debugf("Trying to checkpoint container %s", c.ID())
 
 	if options.TargetFile != "" {
 		if err := c.prepareCheckpointExport(); err != nil {
-			return err
+			return nil, 0, err
 		}
 	}
 
 	if options.WithPrevious {
 		if err := c.canWithPrevious(); err != nil {
-			return err
+			return nil, 0, err
 		}
 	}
 
@@ -817,7 +825,7 @@ func (c *Container) Checkpoint(ctx context.Context, options ContainerCheckpointO
 		defer c.lock.Unlock()
 
 		if err := c.syncContainer(); err != nil {
-			return err
+			return nil, 0, err
 		}
 	}
 	return c.checkpoint(ctx, options)
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 91453574e..2778d2cde 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -1129,25 +1129,26 @@ func (c *Container) checkpointRestoreSupported(version int) error {
 	return nil
 }
 
-func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointOptions) error {
+func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointOptions) (*define.CRIUCheckpointRestoreStatistics, int64, error) {
 	if err := c.checkpointRestoreSupported(criu.MinCriuVersion); err != nil {
-		return err
+		return nil, 0, err
 	}
 
 	if c.state.State != define.ContainerStateRunning {
-		return errors.Wrapf(define.ErrCtrStateInvalid, "%q is not running, cannot checkpoint", c.state.State)
+		return nil, 0, errors.Wrapf(define.ErrCtrStateInvalid, "%q is not running, cannot checkpoint", c.state.State)
 	}
 
 	if c.AutoRemove() && options.TargetFile == "" {
-		return errors.Errorf("cannot checkpoint containers that have been started with '--rm' unless '--export' is used")
+		return nil, 0, errors.Errorf("cannot checkpoint containers that have been started with '--rm' unless '--export' is used")
 	}
 
 	if err := crutils.CRCreateFileWithLabel(c.bundlePath(), "dump.log", c.MountLabel()); err != nil {
-		return err
+		return nil, 0, err
 	}
 
-	if err := c.ociRuntime.CheckpointContainer(c, options); err != nil {
-		return err
+	runtimeCheckpointDuration, err := c.ociRuntime.CheckpointContainer(c, options)
+	if err != nil {
+		return nil, 0, err
 	}
 
 	// Save network.status. This is needed to restore the container with
@@ -1155,7 +1156,7 @@ func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointO
 	// with one interface.
 	// FIXME: will this break something?
 	if _, err := metadata.WriteJSONFile(c.getNetworkStatus(), c.bundlePath(), metadata.NetworkStatusFile); err != nil {
-		return err
+		return nil, 0, err
 	}
 
 	defer c.newContainerEvent(events.Checkpoint)
@@ -1165,13 +1166,13 @@ func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointO
 	if options.WithPrevious {
 		os.Remove(path.Join(c.CheckpointPath(), "parent"))
 		if err := os.Symlink("../pre-checkpoint", path.Join(c.CheckpointPath(), "parent")); err != nil {
-			return err
+			return nil, 0, err
 		}
 	}
 
 	if options.TargetFile != "" {
 		if err := c.exportCheckpoint(options); err != nil {
-			return err
+			return nil, 0, err
 		}
 	}
 
@@ -1183,8 +1184,35 @@ func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointO
 
 		// Cleanup Storage and Network
 		if err := c.cleanup(ctx); err != nil {
-			return err
+			return nil, 0, err
+		}
+	}
+
+	criuStatistics, err := func() (*define.CRIUCheckpointRestoreStatistics, error) {
+		if !options.PrintStats {
+			return nil, nil
+		}
+		statsDirectory, err := os.Open(c.bundlePath())
+		if err != nil {
+			return nil, errors.Wrapf(err, "Not able to open %q", c.bundlePath())
+		}
+
+		dumpStatistics, err := stats.CriuGetDumpStats(statsDirectory)
+		if err != nil {
+			return nil, errors.Wrap(err, "Displaying checkpointing statistics not possible")
 		}
+
+		return &define.CRIUCheckpointRestoreStatistics{
+			FreezingTime: dumpStatistics.GetFreezingTime(),
+			FrozenTime:   dumpStatistics.GetFrozenTime(),
+			MemdumpTime:  dumpStatistics.GetMemdumpTime(),
+			MemwriteTime: dumpStatistics.GetMemwriteTime(),
+			PagesScanned: dumpStatistics.GetPagesScanned(),
+			PagesWritten: dumpStatistics.GetPagesWritten(),
+		}, nil
+	}()
+	if err != nil {
+		return nil, 0, err
 	}
 
 	if !options.Keep && !options.PreCheckPoint {
@@ -1203,7 +1231,7 @@ func (c *Container) checkpoint(ctx context.Context, options ContainerCheckpointO
 	}
 
 	c.state.FinishedTime = time.Now()
-	return c.save()
+	return criuStatistics, runtimeCheckpointDuration, c.save()
 }
 
 func (c *Container) importCheckpoint(input string) error {
diff --git a/libpod/define/checkpoint_restore.go b/libpod/define/checkpoint_restore.go
new file mode 100644
index 000000000..536bdde9a
--- /dev/null
+++ b/libpod/define/checkpoint_restore.go
@@ -0,0 +1,32 @@
+package define
+
+// This contains values reported by CRIU during
+// checkpointing or restoring.
+// All names are the same as reported by CRIU.
+type CRIUCheckpointRestoreStatistics struct {
+	// Checkpoint values
+	// Time required to freeze/pause/quiesce the processes
+	FreezingTime uint32 `json:"freezing_time,omitempty"`
+	// Time the processes are actually not running during checkpointing
+	FrozenTime uint32 `json:"frozen_time,omitempty"`
+	// Time required to extract memory pages from the processes
+	MemdumpTime uint32 `json:"memdump_time,omitempty"`
+	// Time required to write memory pages to disk
+	MemwriteTime uint32 `json:"memwrite_time,omitempty"`
+	// Number of memory pages CRIU analyzed
+	PagesScanned uint64 `json:"pages_scanned,omitempty"`
+	// Number of memory pages written
+	PagesWritten uint64 `json:"pages_written,omitempty"`
+
+	// Restore values
+	// Number of pages compared during restore
+	PagesCompared uint64 `json:"pages_compared,omitempty"`
+	// Number of COW pages skipped during restore
+	PagesSkippedCow uint64 `json:"pages_skipped_cow,omitempty"`
+	// Time required to fork processes
+	ForkingTime uint32 `json:"forking_time,omitempty"`
+	// Time required to restore
+	RestoreTime uint32 `json:"restore_time,omitempty"`
+	// Number of memory pages restored
+	PagesRestored uint64 `json:"pages_restored,omitempty"`
+}
diff --git a/libpod/oci.go b/libpod/oci.go
index c92d9a077..f78600210 100644
--- a/libpod/oci.go
+++ b/libpod/oci.go
@@ -101,8 +101,10 @@ type OCIRuntime interface {
 	// CheckpointContainer checkpoints the given container.
 	// Some OCI runtimes may not support this - if SupportsCheckpoint()
 	// returns false, this is not implemented, and will always return an
-	// error.
-	CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) error
+	// error. If CheckpointOptions.PrintStats is true the first return parameter
+	// contains the number of microseconds the runtime needed to checkpoint
+	// the given container.
+	CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) (int64, error)
 
 	// CheckConmonRunning verifies that the given container's Conmon
 	// instance is still running. Runtimes without Conmon, or systems where
diff --git a/libpod/oci_conmon_linux.go b/libpod/oci_conmon_linux.go
index db906fabb..305d73d75 100644
--- a/libpod/oci_conmon_linux.go
+++ b/libpod/oci_conmon_linux.go
@@ -760,9 +760,9 @@ func (r *ConmonOCIRuntime) AttachResize(ctr *Container, newSize define.TerminalS
 }
 
 // CheckpointContainer checkpoints the given container.
-func (r *ConmonOCIRuntime) CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) error {
+func (r *ConmonOCIRuntime) CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) (int64, error) {
 	if err := label.SetSocketLabel(ctr.ProcessLabel()); err != nil {
-		return err
+		return 0, err
 	}
 	// imagePath is used by CRIU to store the actual checkpoint files
 	imagePath := ctr.CheckpointPath()
@@ -802,14 +802,25 @@ func (r *ConmonOCIRuntime) CheckpointContainer(ctr *Container, options Container
 	}
 	runtimeDir, err := util.GetRuntimeDir()
 	if err != nil {
-		return err
+		return 0, err
 	}
 	if err = os.Setenv("XDG_RUNTIME_DIR", runtimeDir); err != nil {
-		return errors.Wrapf(err, "cannot set XDG_RUNTIME_DIR")
+		return 0, errors.Wrapf(err, "cannot set XDG_RUNTIME_DIR")
 	}
 	args = append(args, ctr.ID())
 	logrus.Debugf("the args to checkpoint: %s %s", r.path, strings.Join(args, " "))
-	return utils.ExecCmdWithStdStreams(os.Stdin, os.Stdout, os.Stderr, nil, r.path, args...)
+
+	runtimeCheckpointStarted := time.Now()
+	err = utils.ExecCmdWithStdStreams(os.Stdin, os.Stdout, os.Stderr, nil, r.path, args...)
+
+	runtimeCheckpointDuration := func() int64 {
+		if options.PrintStats {
+			return time.Since(runtimeCheckpointStarted).Microseconds()
+		}
+		return 0
+	}()
+
+	return runtimeCheckpointDuration, err
 }
 
 func (r *ConmonOCIRuntime) CheckConmonRunning(ctr *Container) (bool, error) {
diff --git a/libpod/oci_missing.go b/libpod/oci_missing.go
index fcf2ffca8..c91146b9c 100644
--- a/libpod/oci_missing.go
+++ b/libpod/oci_missing.go
@@ -153,8 +153,8 @@ func (r *MissingRuntime) ExecUpdateStatus(ctr *Container, sessionID string) (boo
 }
 
 // CheckpointContainer is not available as the runtime is missing
-func (r *MissingRuntime) CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) error {
-	return r.printError()
+func (r *MissingRuntime) CheckpointContainer(ctr *Container, options ContainerCheckpointOptions) (int64, error) {
+	return 0, r.printError()
 }
 
 // CheckConmonRunning is not available as the runtime is missing