Kubernetes/Scheduling - Revision history

Pio2pio: /* node scheduling */

2022-01-06T19:55:08Z

node scheduling

@@ Line 262: / Line 262: @@
 </source>
-= node scheduling =
+== <code>nodeAffinity</code> and <code>podAntiAffinity</code> ==
 This scenario tries to schedule (prefer) on nodes with label "node.kubernetes.io/lifecycle=normal" but also schedule some pods on other nodes (podAntiAffinity) even if nodeAffinity does not match. This is to avoid that all pods would run on the same node (eg. only one node matching nodeAffinity) and other nodes are available.
 <source lang=yaml>
@@ Line 327: / Line 326: @@
 A: 6x pods have scheduled on the preferred nodes (3pods each node), and 4 on other nodes
 = Deamonset =

2022-01-06T19:54:25Z

Tains and tolerations

← Older revision		Revision as of 21:54, 6 January 2022
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	* Kubelet, Docker		* Kubelet, Docker

	= Tains and tolerations =		= Kubernetes pod to node scheduling =
			== Tains and tolerations ==
	* [https://deploy.live/blog/visual-guide-to-node-selectors-taints-and-tolerations/ Visual Guide to Node Selectors, Taints and Tolerations]		* [https://deploy.live/blog/visual-guide-to-node-selectors-taints-and-tolerations/ Visual Guide to Node Selectors, Taints and Tolerations]

2022-01-06T19:50:21Z

Tains and tolerations

← Older revision		Revision as of 21:50, 6 January 2022
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	= Tains and tolerations =		= Tains and tolerations =
			* [https://deploy.live/blog/visual-guide-to-node-selectors-taints-and-tolerations/ Visual Guide to Node Selectors, Taints and Tolerations]


	Tains and tolerations are restrictions to what PODs can be scheduled on nodes. By default Pods have no tolerations set up.		Tains and tolerations are restrictions to what PODs can be scheduled on nodes. By default Pods have no tolerations set up.

2021-03-12T15:58:34Z

Deamonset

@@ Line 257: / Line 257: @@
      effect: NoSchedule
 </source>
 = Deamonset =

2020-01-28T13:26:15Z

Tains and tolerations

@@ Line 210: / Line 210: @@
          memory: 40Mi  #
 </syntaxhighlightjs>
 = Tains and tolerations =

2020-01-28T13:03:18Z

Resource quotas | Resource request and limit

← Older revision		Revision as of 15:03, 28 January 2020
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	* cpu <code>250m</code> - measured in ''cores'', it means 250 miliCPUs or 0.25 CPU core		* cpu <code>250m</code> - measured in ''cores'', it means 250 miliCPUs or 0.25 CPU core
	Note: 1 MiB = 2<sup>20</sup> bytes = 1048576bytes = 1024 kibibytes		Note: 1 MiB = 2<sup>20</sup> bytes = 1048576bytes = 1024 kibibytes


			Requests and limits
			<source lang=bash>
			spec:
			containers:
			- name: hello-world-container
			image: paulbouwer/hello-kubernetes:1.5
			resources:
			limits:
			cpu: "0.9" # Throttling if tries to use more
			memory: 512Mi # OOM kill if tries to use more
			requests:
			cpu: "500m" # Info for scheduling and Docker. Chances for
			memory: 256Mi # eviction increase if we use more than requested.
			</source>

2019-12-18T14:42:04Z

Resource request and limit

← Older revision		Revision as of 16:42, 18 December 2019
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	</syntaxhighlightjs>		</syntaxhighlightjs>

	== [https://medium.com/@betz.mark/understanding-resource-limits-in-kubernetes-cpu-time-9eff74d3161b Resource request and limit] ==		== [https://kubernetes.io/docs/concepts/policy/resource-quotas/#enabling-resource-quota Resource quotas] \| [https://medium.com/@betz.mark/understanding-resource-limits-in-kubernetes-cpu-time-9eff74d3161b Resource request and limit] ==
	;resource request: is what a '''pods is guaranteed to get'''; it's the amount of resources necessary to run a container; a pod will only be scheduled on a node that can give that resource		;resource request: is what a '''pods is guaranteed to get'''; it's the amount of resources necessary to run a container; a pod will only be scheduled on a node that can give that resource
	;resource limit: makes sure that a container never goes above a value specified, they allow to up to the limit then are resticted		;resource limit: makes sure that a container never goes above a value specified, they allow to up to the limit then are resticted

2019-12-18T13:00:53Z

Resource request and limit

← Older revision		Revision as of 15:00, 18 December 2019
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	* 1 AWS vCPU, 1 GCP Core, 1 Azure vCore, 1 IBM vCPU		* 1 AWS vCPU, 1 GCP Core, 1 Azure vCore, 1 IBM vCPU
	* 1 Hyperthread on a bare-metal Intel processor with Hyperthreading		* 1 Hyperthread on a bare-metal Intel processor with Hyperthreading
			* CPU is always requested as an absolute quantity, never as a relative quantity; 0.1 is the same amount of CPU on a single-core, dual-core, or 48-core machine.

2019-12-18T12:03:48Z

Resource request and limit

← Older revision		Revision as of 14:03, 18 December 2019
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	* '''Exceeding a memory limit''' makes your container process a candidate for ''oom-killing''		* '''Exceeding a memory limit''' makes your container process a candidate for ''oom-killing''
	* process basically can’t '''exceed the set cpu quota''', and will never get evicted for trying to use more cpu time than allocated. The system enforces the quota at the scheduler so the process just gets throttled at the limit.		* process basically can’t '''exceed the set cpu quota''', and will never get evicted for trying to use more cpu time than allocated. The system enforces the quota at the scheduler so the process just gets throttled at the limit.


			Limits and requests for CPU resources are measured in cpu units. One cpu, in Kubernetes, is equivalent to:
			* 1 AWS vCPU, 1 GCP Core, 1 Azure vCore, 1 IBM vCPU
			* 1 Hyperthread on a bare-metal Intel processor with Hyperthreading

2019-12-18T11:47:22Z

Resource request and limit

← Older revision		Revision as of 13:47, 18 December 2019
Line 105:		Line 105:
	* '''Exceeding a memory limit''' makes your container process a candidate for ''oom-killing''		* '''Exceeding a memory limit''' makes your container process a candidate for ''oom-killing''
	* process basically can’t '''exceed the set cpu quota''', and will never get evicted for trying to use more cpu time than allocated. The system enforces the quota at the scheduler so the process just gets throttled at the limit.		* process basically can’t '''exceed the set cpu quota''', and will never get evicted for trying to use more cpu time than allocated. The system enforces the quota at the scheduler so the process just gets throttled at the limit.


			Resources type (compressed and not-compressed resource)
			* CPU (compressed resource) - once limit has been reached Kubernetes will start throttling CPU of the container process(es). The pod won't get terminated or evicted
			* Memory (''not compressible resource'') - once limit has been reached the pod will get '''terminated'''