wip

agent/app/agent.go

@@ -145,6 +145,9 @@ func newAgent(
 		metadataManager = containermetadata.NewManager(dockerClient, cfg)
 	}
 
+	resource := resources.New()
+	resource.ApplyConfigDependencies(cfg)
+
 	return &ecsAgent{
 		ctx:               ctx,
 		ec2MetadataClient: ec2MetadataClient,
@@ -163,7 +166,7 @@ func newAgent(
 		}),
 		os:                 oswrapper.New(),
 		metadataManager:    metadataManager,
-		resource:           resources.New(),
+		resource:           resource,
 		terminationHandler: sighandlers.StartDefaultTerminationHandler,
 	}, nil
 }

agent/config/config.go

@@ -280,6 +280,8 @@ func environmentConfig() (Config, error) {
 
 	dockerStopTimeout := getDockerStopTimeout()
 
+	cgroupMemorySubsystemPath := os.Getenv("ECS_CGROUP_MEMORY_SUBSYSTEM_PATH")
+
 	taskCleanupWaitDuration := parseEnvVariableDuration("ECS_ENGINE_TASK_CLEANUP_WAIT_DURATION")
 
 	availableLoggingDriversEnv := os.Getenv("ECS_AVAILABLE_LOGGING_DRIVERS")
@@ -388,6 +390,7 @@ func environmentConfig() (Config, error) {
 		ContainerMetadataEnabled:         containerMetadataEnabled,
 		DataDirOnHost:                    dataDirOnHost,
 		OverrideAWSLogsExecutionRole:     overrideAWSLogsExecutionRoleEnabled,
+		CgroupMemorySubsystemPath:        cgroupMemorySubsystemPath,
 	}, err
 }
 

agent/config/config_unix.go

@@ -27,6 +27,8 @@ const (
 	defaultCredentialsAuditLogFile = "/log/audit.log"
 	// Default cgroup prefix for ECS tasks
 	DefaultTaskCgroupPrefix = "/ecs"
+
+	defaultCgroupMemorySubsystemPath = "/sys/fs/cgroup/memory/"
 )
 
 // DefaultConfig returns the default configuration for Linux
@@ -55,6 +57,7 @@ func DefaultConfig() Config {
 		AWSVPCBlockInstanceMetdata:  false,
 		ContainerMetadataEnabled:    false,
 		TaskCPUMemLimit:             DefaultEnabled,
+		CgroupMemorySubsystemPath:   defaultCgroupMemorySubsystemPath,
 	}
 }
 

agent/config/types.go

@@ -194,4 +194,6 @@ type Config struct {
 	// OverrideAWSLogsExecutionRole is config option used to enable awslogs
 	// driver authentication over the task's execution role
 	OverrideAWSLogsExecutionRole bool
+
+	CgroupMemorySubsystemPath string
 }

agent/engine/task_manager.go

@@ -105,12 +105,14 @@ type managedTask struct {
 // This method must only be called when the engine.processTasks write lock is
 // already held.
 func (engine *DockerTaskEngine) newManagedTask(task *api.Task) *managedTask {
+	resource := resources.New()
+	resource.ApplyConfigDependencies(engine.cfg)
 	t := &managedTask{
 		Task:           task,
 		acsMessages:    make(chan acsTransition),
 		dockerMessages: make(chan dockerContainerChange),
 		engine:         engine,
-		resource:       resources.New(),
+		resource:       resource,
 	}
 	engine.managedTasks[task.Arn] = t
 	return t

agent/resources/interface.go

@@ -15,6 +15,7 @@ package resources
 
 import (
 	"github.com/aws/amazon-ecs-agent/agent/api"
+	"github.com/aws/amazon-ecs-agent/agent/config"
 )
 
 // Resource interface to interact with platform level resource constructs
@@ -26,4 +27,6 @@ type Resource interface {
 	Setup(task *api.Task) error
 	// Cleanup removes the resource
 	Cleanup(task *api.Task) error
+
+	ApplyConfigDependencies(cfg *config.Config)
 }

agent/resources/resources_linux.go

@@ -30,14 +30,14 @@ import (
 )
 
 const (
-	memorySubsystem    = "/sys/fs/cgroup/memory/"
 	memoryUseHierarchy = "memory.use_hierarchy"
 )
 
 // cgroupWrapper implements the Resource interface
 type cgroupWrapper struct {
-	control cgroup.Control
-	ioutil  ioutilwrapper.IOUtil
+	control             cgroup.Control
+	ioutil              ioutilwrapper.IOUtil
+	memorySubsystemPath string
 }
 
 // New is used to return an object that implements the Resource interface
@@ -67,6 +67,10 @@ func (c *cgroupWrapper) Cleanup(task *api.Task) error {
 	return c.cleanupCgroup(task)
 }
 
+func (c *cgroupWrapper) ApplyConfigDependencies(cfg *config.Config) {
+	c.memorySubsystemPath = cfg.CgroupMemorySubsystemPath
+}
+
 // cgroupInit is used to create the root '/ecs/ cgroup
 func (c *cgroupWrapper) cgroupInit() error {
 	if c.control.Exists(config.DefaultTaskCgroupPrefix) {
@@ -106,6 +110,8 @@ func (c *cgroupWrapper) setupCgroup(task *api.Task) error {
 	}
 
 	// echo 1 > memory.use_hierarchy
+	memorySubsystem := c.memorySubsystemPath
+
 	err = c.ioutil.WriteFile(filepath.Join(memorySubsystem, cgroupRoot, memoryUseHierarchy), []byte(strconv.Itoa(1)), os.FileMode(0))
 	if err != nil {
 		return errors.Wrapf(err, "resource: setup cgroup: unable to set use hierarchy flag for task: %s", task.Arn)