libpod: do not call (*container).Config()

Access the container's config field directly inside of libpod instead of
calling `Config()` which in turn creates expensive JSON deep copies.

Accessing the field directly drops memory consumption of a simple
`podman run --rm busybox true` from 1245kB to 410kB.

[NO TESTS NEEDED]

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

<MH: Fixed cherry-pick conflicts>

1 files changed, 3 insertions, 4 deletions

diff --git a/libpod/container_internal.go b/libpod/container_internal.go
index 18b80475b..2ca49758d 100644
--- a/libpod/container_internal.go
+++ b/libpod/container_internal.go
@@ -982,12 +982,11 @@ func (c *Container) checkDependenciesRunning() ([]string, error) {
 		}
 
 		// Check the status
-		conf := depCtr.Config()
 		state, err := depCtr.State()
 		if err != nil {
 			return nil, errors.Wrapf(err, "error retrieving state of dependency %s of container %s", dep, c.ID())
 		}
-		if state != define.ContainerStateRunning && !conf.IsInfra {
+		if state != define.ContainerStateRunning && !depCtr.config.IsInfra {
 			notRunning = append(notRunning, dep)
 		}
 		depCtrs[dep] = depCtr
@@ -1063,7 +1062,7 @@ func (c *Container) cniHosts() string {
 	var hosts string
 	if len(c.state.NetworkStatus) > 0 && len(c.state.NetworkStatus[0].IPs) > 0 {
 		ipAddress := strings.Split(c.state.NetworkStatus[0].IPs[0].Address.String(), "/")[0]
-		hosts += fmt.Sprintf("%s\t%s %s\n", ipAddress, c.Hostname(), c.Config().Name)
+		hosts += fmt.Sprintf("%s\t%s %s\n", ipAddress, c.Hostname(), c.config.Name)
 	}
 	return hosts
 }
@@ -2127,7 +2126,7 @@ func (c *Container) canWithPrevious() error {
 // JSON files for later export
 func (c *Container) prepareCheckpointExport() error {
 	// save live config
-	if _, err := metadata.WriteJSONFile(c.Config(), c.bundlePath(), metadata.ConfigDumpFile); err != nil {
+	if _, err := metadata.WriteJSONFile(c.config, c.bundlePath(), metadata.ConfigDumpFile); err != nil {
 		return err
 	}