Added optional container restore statistics

This adds the parameter '--print-stats' to 'podman container restore'.
With '--print-stats' Podman will measure how long Podman itself, the OCI
runtime and CRIU requires to restore a checkpoint and print out these
information. CRIU already creates process restore statistics which are
just read in addition to the added measurements. In contrast to just
printing out the ID of the restored container, Podman will now print
out JSON:

 # podman container restore --latest --print-stats
 {
     "podman_restore_duration": 305871,
     "container_statistics": [
         {
             "Id": "47b02e1d474b5d5fe917825e91ac653efa757c91e5a81a368d771a78f6b5ed20",
             "runtime_restore_duration": 140614,
             "criu_statistics": {
                 "forking_time": 5,
                 "restore_time": 67672,
                 "pages_restored": 14
             }
         }
     ]
 }

The output contains 'podman_restore_duration' which contains the
number of microseconds Podman required to restore the checkpoint. The
output also includes 'runtime_restore_duration' which is the time
the runtime needed to restore that specific container. Each container
also includes 'criu_statistics' which displays the timing information
collected by CRIU.

Signed-off-by: Adrian Reber <areber@redhat.com>

2 files changed, 16 insertions, 2 deletions

diff --git a/pkg/api/handlers/libpod/containers.go b/pkg/api/handlers/libpod/containers.go
index d8312e9be..3aeebc334 100644
--- a/pkg/api/handlers/libpod/containers.go
+++ b/pkg/api/handlers/libpod/containers.go
@@ -294,6 +294,7 @@ func Restore(w http.ResponseWriter, r *http.Request) {
 		IgnoreVolumes   bool   `schema:"ignoreVolumes"`
 		IgnoreStaticIP  bool   `schema:"ignoreStaticIP"`
 		IgnoreStaticMAC bool   `schema:"ignoreStaticMAC"`
+		PrintStats      bool   `schema:"printStats"`
 	}{
 		// override any golang type defaults
 	}
@@ -329,17 +330,26 @@ func Restore(w http.ResponseWriter, r *http.Request) {
 		IgnoreRootfs:    query.IgnoreRootFS,
 		IgnoreStaticIP:  query.IgnoreStaticIP,
 		IgnoreStaticMAC: query.IgnoreStaticMAC,
+		PrintStats:      query.PrintStats,
 	}
 	if query.Import {
 		options.TargetFile = targetFile
 		options.Name = query.Name
 	}
-	err = ctr.Restore(r.Context(), options)
+	criuStatistics, runtimeRestoreDuration, err := ctr.Restore(r.Context(), options)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return
 	}
-	utils.WriteResponse(w, http.StatusOK, entities.RestoreReport{Id: ctr.ID()})
+	utils.WriteResponse(
+		w,
+		http.StatusOK,
+		entities.RestoreReport{
+			Id:              ctr.ID(),
+			RuntimeDuration: runtimeRestoreDuration,
+			CRIUStatistics:  criuStatistics,
+		},
+	)
 }
 
 func InitContainer(w http.ResponseWriter, r *http.Request) {
diff --git a/pkg/api/server/register_containers.go b/pkg/api/server/register_containers.go
index e98098f97..601e1251b 100644
--- a/pkg/api/server/register_containers.go
+++ b/pkg/api/server/register_containers.go
@@ -1499,6 +1499,10 @@ func (s *APIServer) registerContainersHandlers(r *mux.Router) error {
 	//    name: ignoreStaticMAC
 	//    type: boolean
 	//    description: ignore MAC address if set statically
+	//  - in: query
+	//    name: printStats
+	//    type: boolean
+	//    description: add restore statistics to the returned RestoreReport
 	// produces:
 	// - application/json
 	// responses: