integ/kubernetes/kubernetes-1.29.2/debian/deb_folder/patches/kubeadm-create-platform-pods-with-zero-CPU-resources.patch
Jim Gauld 45d5e92488 Modify kube-apiserver cpu resource limits and readiness probes
This refactors the existing Kubernetes patch
kubeadm-create-platform-pods-with-zero-CPU-resources.patch.
This now modifies kube-apiserver pod to be burstable, and to
have relaxed Readiness probe settings.

This specifies CPU limit of 1 for kube-apiserver pod so that it is
treated as a burstable QoS. This gives a boost of cgroup CPUShares
since the burstable cgroup parent has significantly more CPUShares
than best-effort on typical systems. This improves kube-apiserver
API responsiveness.

This increases kube-apiserver Readiness probe periodSeconds to 10
based on WRS/SS joint recommendation for minimum probe settings.
This reduces likelihood of kube-apiserver probe failure and
subsequent pod-restart under servere load. This also reduces CPU
demand.

Partial-Bug: 2084714

TEST PLAN:
- PASS: AIO-SX: Fresh install with each k8s version
        v1.24.4, 1.25.3, 1.26.1, 1.27.5, 1.28.4, 1.29.2,
        verify kube-apiserver pod is burstable QoS and
        has Readiness probe periodSeconds 10
  e.g.,
  kubectl get pod -n kube-system kube-apisever-controller-0 -oyaml
  sudo kube-cpusets

- PASS: AIO-SX: orchestrated K8S upgrade from 1.24.4 to 1.29.2

Change-Id: Ic327b6c176c3a98c16afd14e6bc001315d7cbdc0
Signed-off-by: Jim Gauld <James.Gauld@windriver.com>
2024-11-08 16:05:32 -05:00

171 lines
8.7 KiB
Diff

From 668dc57e7c06da9b29dd677648fdb198901332a1 Mon Sep 17 00:00:00 2001
From: Boovan Rajendran <boovan.rajendran@windriver.com>
Date: Mon, 26 Feb 2024 04:40:48 -0500
Subject: [PATCH] kubeadm: create platform pods with zero CPU resources
This specifies zero CPU resources when creating the manifests
for the static platform pods, as a workaround for the lack of
separate resource tracking for platform resources.
This specifies zero CPU and Memory resources for the coredns
deployment. manifests.go is the main source file for this,
not sure if the coredns.yaml are used but they are updated to
be consistent.
This specifies CPU limit of 1 for kube-apiserver pod so that it is
treated as a burstable QoS. This gives a boost of cgroup CPUShares
since the burstable cgroup parent has significantly more CPUShares
than best-effort on typical systems. This improves kube-apiserver
API responsiveness.
This increases kube-apiserver Readiness probe periodSeconds to 10
based on WRS/SS joint recommendation for minimum probe settings.
This reduces likelihood of kube-apiserver probe failure and
subsequent pod-restart under servere load. This also reduces CPU
demand.
Signed-off-by: Daniel Safta <daniel.safta@windriver.com>
Signed-off-by: Saba Touheed Mujawar <sabatouheed.mujawar@windriver.com>
Signed-off-by: Boovan Rajendran <boovan.rajendran@windriver.com>
Signed-off-by: Jim Gauld <James.Gauld@windriver.com>
---
cluster/addons/dns/coredns/coredns.yaml.base | 4 ++--
cluster/addons/dns/coredns/coredns.yaml.in | 4 ++--
cluster/addons/dns/coredns/coredns.yaml.sed | 4 ++--
cmd/kubeadm/app/phases/addons/dns/manifests.go | 4 ++--
.../app/phases/controlplane/manifests.go | 8 +++++---
cmd/kubeadm/app/util/staticpod/utils.go | 17 ++++++++++++++++-
6 files changed, 29 insertions(+), 12 deletions(-)
diff --git a/cluster/addons/dns/coredns/coredns.yaml.base b/cluster/addons/dns/coredns/coredns.yaml.base
index dd4570adb65..3a0fd7adb72 100644
--- a/cluster/addons/dns/coredns/coredns.yaml.base
+++ b/cluster/addons/dns/coredns/coredns.yaml.base
@@ -139,8 +139,8 @@ spec:
limits:
memory: __DNS__MEMORY__LIMIT__
requests:
- cpu: 100m
- memory: 70Mi
+ cpu: 0
+ memory: 0
args: [ "-conf", "/etc/coredns/Corefile" ]
volumeMounts:
- name: config-volume
diff --git a/cluster/addons/dns/coredns/coredns.yaml.in b/cluster/addons/dns/coredns/coredns.yaml.in
index 6939faec3f9..74b59584bc7 100644
--- a/cluster/addons/dns/coredns/coredns.yaml.in
+++ b/cluster/addons/dns/coredns/coredns.yaml.in
@@ -139,8 +139,8 @@ spec:
limits:
memory: 'dns_memory_limit'
requests:
- cpu: 100m
- memory: 70Mi
+ cpu: 0
+ memory: 0
args: [ "-conf", "/etc/coredns/Corefile" ]
volumeMounts:
- name: config-volume
diff --git a/cluster/addons/dns/coredns/coredns.yaml.sed b/cluster/addons/dns/coredns/coredns.yaml.sed
index a90f2b7674a..61afbecd9da 100644
--- a/cluster/addons/dns/coredns/coredns.yaml.sed
+++ b/cluster/addons/dns/coredns/coredns.yaml.sed
@@ -139,8 +139,8 @@ spec:
limits:
memory: $DNS_MEMORY_LIMIT
requests:
- cpu: 100m
- memory: 70Mi
+ cpu: 0
+ memory: 0
args: [ "-conf", "/etc/coredns/Corefile" ]
volumeMounts:
- name: config-volume
diff --git a/cmd/kubeadm/app/phases/addons/dns/manifests.go b/cmd/kubeadm/app/phases/addons/dns/manifests.go
index 905a2e050e6..2a2212d5d37 100644
--- a/cmd/kubeadm/app/phases/addons/dns/manifests.go
+++ b/cmd/kubeadm/app/phases/addons/dns/manifests.go
@@ -104,8 +104,8 @@ spec:
limits:
memory: 170Mi
requests:
- cpu: 100m
- memory: 70Mi
+ cpu: 0
+ memory: 0
args: [ "-conf", "/etc/coredns/Corefile" ]
volumeMounts:
- name: config-volume
diff --git a/cmd/kubeadm/app/phases/controlplane/manifests.go b/cmd/kubeadm/app/phases/controlplane/manifests.go
index 998ca2e3456..7988f1fe918 100644
--- a/cmd/kubeadm/app/phases/controlplane/manifests.go
+++ b/cmd/kubeadm/app/phases/controlplane/manifests.go
@@ -66,7 +66,9 @@ func GetStaticPodSpecs(cfg *kubeadmapi.ClusterConfiguration, endpoint *kubeadmap
LivenessProbe: staticpodutil.LivenessProbe(staticpodutil.GetAPIServerProbeAddress(endpoint), "/livez", endpoint.BindPort, v1.URISchemeHTTPS),
ReadinessProbe: staticpodutil.ReadinessProbe(staticpodutil.GetAPIServerProbeAddress(endpoint), "/readyz", endpoint.BindPort, v1.URISchemeHTTPS),
StartupProbe: staticpodutil.StartupProbe(staticpodutil.GetAPIServerProbeAddress(endpoint), "/livez", endpoint.BindPort, v1.URISchemeHTTPS, cfg.APIServer.TimeoutForControlPlane),
- Resources: staticpodutil.ComponentResources("250m"),
+ // WRS: Increase kube-apiserver cgroup CPUShares to improve API responsiveness;
+ // achieved by setting CPU Limits to make it burstable QoS.
+ Resources: staticpodutil.ComponentLimitResources("0", "1"),
Env: kubeadmutil.MergeKubeadmEnvVars(proxyEnvs, cfg.APIServer.ExtraEnvs),
}, mounts.GetVolumes(kubeadmconstants.KubeAPIServer),
map[string]string{kubeadmconstants.KubeAPIServerAdvertiseAddressEndpointAnnotationKey: endpoint.String()}),
@@ -78,7 +80,7 @@ func GetStaticPodSpecs(cfg *kubeadmapi.ClusterConfiguration, endpoint *kubeadmap
VolumeMounts: staticpodutil.VolumeMountMapToSlice(mounts.GetVolumeMounts(kubeadmconstants.KubeControllerManager)),
LivenessProbe: staticpodutil.LivenessProbe(staticpodutil.GetControllerManagerProbeAddress(cfg), "/healthz", kubeadmconstants.KubeControllerManagerPort, v1.URISchemeHTTPS),
StartupProbe: staticpodutil.StartupProbe(staticpodutil.GetControllerManagerProbeAddress(cfg), "/healthz", kubeadmconstants.KubeControllerManagerPort, v1.URISchemeHTTPS, cfg.APIServer.TimeoutForControlPlane),
- Resources: staticpodutil.ComponentResources("200m"),
+ Resources: staticpodutil.ComponentResources("0"),
Env: kubeadmutil.MergeKubeadmEnvVars(proxyEnvs, cfg.ControllerManager.ExtraEnvs),
}, mounts.GetVolumes(kubeadmconstants.KubeControllerManager), nil),
kubeadmconstants.KubeScheduler: staticpodutil.ComponentPod(v1.Container{
@@ -89,7 +91,7 @@ func GetStaticPodSpecs(cfg *kubeadmapi.ClusterConfiguration, endpoint *kubeadmap
VolumeMounts: staticpodutil.VolumeMountMapToSlice(mounts.GetVolumeMounts(kubeadmconstants.KubeScheduler)),
LivenessProbe: staticpodutil.LivenessProbe(staticpodutil.GetSchedulerProbeAddress(cfg), "/healthz", kubeadmconstants.KubeSchedulerPort, v1.URISchemeHTTPS),
StartupProbe: staticpodutil.StartupProbe(staticpodutil.GetSchedulerProbeAddress(cfg), "/healthz", kubeadmconstants.KubeSchedulerPort, v1.URISchemeHTTPS, cfg.APIServer.TimeoutForControlPlane),
- Resources: staticpodutil.ComponentResources("100m"),
+ Resources: staticpodutil.ComponentResources("0"),
Env: kubeadmutil.MergeKubeadmEnvVars(proxyEnvs, cfg.Scheduler.ExtraEnvs),
}, mounts.GetVolumes(kubeadmconstants.KubeScheduler), nil),
}
diff --git a/cmd/kubeadm/app/util/staticpod/utils.go b/cmd/kubeadm/app/util/staticpod/utils.go
index ea2b13f4b16..6f9afebf348 100644
--- a/cmd/kubeadm/app/util/staticpod/utils.go
+++ b/cmd/kubeadm/app/util/staticpod/utils.go
@@ -99,6 +99,18 @@ func ComponentResources(cpu string) v1.ResourceRequirements {
}
}
+// ComponentLimitResources returns the v1.ResourceRequirements object needed for allocating a specified amount of the CPU with Limits
+func ComponentLimitResources(cpu string, lcpu string) v1.ResourceRequirements {
+ return v1.ResourceRequirements{
+ Requests: v1.ResourceList{
+ v1.ResourceCPU: resource.MustParse(cpu),
+ },
+ Limits: v1.ResourceList{
+ v1.ResourceCPU: resource.MustParse(lcpu),
+ },
+ }
+}
+
// NewVolume creates a v1.Volume with a hostPath mount to the specified location
func NewVolume(name, path string, pathType *v1.HostPathType) v1.Volume {
return v1.Volume{
@@ -255,7 +267,10 @@ func LivenessProbe(host, path string, port int32, scheme v1.URIScheme) *v1.Probe
func ReadinessProbe(host, path string, port int32, scheme v1.URIScheme) *v1.Probe {
// sets initialDelaySeconds as '0' because we don't want to delay user infrastructure checks
// looking for "ready" status on kubeadm static Pods
- return createHTTPProbe(host, path, port, scheme, 0, 15, 3, 1)
+ // WRS/SS joint recommendation: All pods probes should have following minimum probe
+ // settings unless required by the service (initialDelaySecond 0, periodSeconds 10,
+ // timeoutSeconds 5, successThreshold 1, failureThreshold 3)
+ return createHTTPProbe(host, path, port, scheme, 0, 15, 3, 10)
}
// StartupProbe creates a Probe object with a HTTPGet handler
--
2.25.1