Add a flag to set OOMScore

fix #337
Signed-off-by: yanxuean <yan.xuean@zte.com.cn>

cmd/cri-containerd/options/options.go

@@ -82,6 +82,8 @@ type Config struct {
 	StatsCollectPeriod int `toml:"stats_collect_period"`
 	// SystemdCgroup enables systemd cgroup support.
 	SystemdCgroup bool `toml:"systemd_cgroup"`
+	// OOMScore adjust the cri-containerd's oom score
+	OOMScore int `toml:"oom_score"`
 }
 
 // CRIContainerdOptions contains cri-containerd command line and toml options.
@@ -143,6 +145,8 @@ func (c *CRIContainerdOptions) AddFlags(fs *pflag.FlagSet) {
 		false, "Enables systemd cgroup support. By default not enabled.")
 	fs.BoolVar(&c.PrintDefaultConfig, "default-config",
 		false, "Print default toml config of cri-containerd and quit.")
+	fs.IntVar(&c.OOMScore, "oom-score",
+		-999, "Adjust the cri-containerd's oom score.")
 }
 
 // InitFlags must be called after adding all cli options flags are defined and

pkg/server/service.go

@@ -29,6 +29,7 @@ import (
 	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/images"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/sys"
 	"github.com/cri-o/ocicni/pkg/ocicni"
 	"github.com/golang/glog"
 	runcapparmor "github.com/opencontainers/runc/libcontainer/apparmor"
@@ -121,6 +122,11 @@ func NewCRIContainerdService(config options.Config) (CRIContainerdService, error
 			return nil, fmt.Errorf("failed to load cgroup for cgroup path %v: %v", config.CgroupPath, err)
 		}
 	}
+	if config.OOMScore != 0 {
+		if err := sys.SetOOMScore(os.Getpid(), config.OOMScore); err != nil {
+			return nil, fmt.Errorf("failed to set OOMScore to %v: %v", config.OOMScore, err)
+		}
+	}
 
 	c := &criContainerdService{
 		config:              config,