Add node pressure eviction

main.go

@@ -18,20 +18,21 @@ package main
 
 import (
 	"fmt"
-	"github.com/EdgeNet-project/node/pkg/cluster"
-	"github.com/EdgeNet-project/node/pkg/network"
-	"github.com/EdgeNet-project/node/pkg/platforms"
-	"github.com/EdgeNet-project/node/pkg/utils"
-	"github.com/thanhpk/randstr"
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-	"gopkg.in/yaml.v3"
 	"log"
 	"math/rand"
 	"net"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
+
+	"github.com/EdgeNet-project/node/pkg/cluster"
+	"github.com/EdgeNet-project/node/pkg/network"
+	"github.com/EdgeNet-project/node/pkg/platforms"
+	"github.com/EdgeNet-project/node/pkg/utils"
+	"github.com/thanhpk/randstr"
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+	"gopkg.in/yaml.v3"
 )
 
 const defaultKubeconfigURL = "https://raw.githubusercontent.com/EdgeNet-project/edgenet/master/configs/public.cfg"
@@ -238,6 +239,10 @@ func main() {
 	network.SetKubeletNodeIP(kubeletEnvFileDebian, nodeIP)
 	network.SetKubeletNodeIP(kubeletEnvFileRedHat, nodeIP)
 
+	log.Println("step=set-node-pressure-eviction")
+	cluster.SetKubeletNodePressureEviction(kubeletEnvFileDebian)
+	cluster.SetKubeletNodePressureEviction(kubeletEnvFileRedHat)
+
 	log.Println("step=join-cluster")
 	cluster.Join(defaultKubeconfigURL, hostname, nodeIP)
 }

pkg/cluster/cluster.go

@@ -18,19 +18,20 @@ package cluster
 
 import (
 	"context"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+	"strings"
+
 	"github.com/EdgeNet-project/edgenet/pkg/apis/core/v1alpha"
 	v1alpha2 "github.com/EdgeNet-project/edgenet/pkg/apis/networking/v1alpha"
 	"github.com/EdgeNet-project/edgenet/pkg/generated/clientset/versioned"
 	"github.com/EdgeNet-project/node/pkg/utils"
-	"io/ioutil"
 	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
-	"log"
-	"net"
-	"net/http"
-	"strings"
 )
 
 func check(err error) {
@@ -133,3 +134,31 @@ func Join(configURL string, hostname string, externalIP net.IP) {
 		log.Print("node-contribution-status=created")
 	}
 }
+
+// SetKubeletNodePressureEviction sets the eviction thresholds, system reserved resources and minimum reclaim in the kubelet configuration.
+func SetKubeletNodePressureEviction(kubeletEnvFile string) {
+	if dat, err := ioutil.ReadFile(kubeletEnvFile); err == nil {
+		// TODO: Set these parameters via the config file specified by the Kubelet's --config flag.
+		// https://kubernetes.io/docs/tasks/administer-cluster/kubelet-config-file/
+		// TODO: Dynamically assign system reserved memory as 10% (X%) of the capacity.
+		kubeletConfig := string(dat)
+
+		splitFn := func(c rune) bool {
+			return c == '"'
+		}
+		split := strings.FieldsFunc(kubeletConfig, splitFn)
+
+		parameters := "--eviction-hard=memory.available<250Mi,nodefs.available<10%%,imagefs.available<15%% --system-reserved=cpu=200m,memory=500Mi --eviction-minimum-reclaim=memory.available=0Mi,nodefs.available=500Mi,imagefs.available=2Gi "
+		for key, value := range split {
+			if key == 0 {
+				kubeletConfig = value + "\"" + parameters
+			} else if key != len(split)-1 {
+				kubeletConfig += value
+			} else {
+				kubeletConfig += value + "\"\n"
+			}
+		}
+
+		check(ioutil.WriteFile(kubeletEnvFile, []byte(kubeletConfig), 0644))
+	}
+}

pkg/network/network.go

@@ -19,14 +19,15 @@ package network
 import (
 	"errors"
 	"fmt"
-	"github.com/txn2/txeh"
-	"github.com/vishvananda/netlink"
-	"golang.org/x/sys/unix"
 	"io/ioutil"
 	"net"
 	"os"
 	"os/exec"
 	"strings"
+
+	"github.com/txn2/txeh"
+	"github.com/vishvananda/netlink"
+	"golang.org/x/sys/unix"
 )
 
 func check(err error) {