Re: [kubernetes-users] Resource requests/limits on Pod-level

['Vishnu Kannan' via Kubernetes user discussion and Q]

As davidopp@ mentioned a pod is the unit of scheduling. So to find a
suitable node for a pod, the scheduler has to identify a node that sum(all
container requests) available.

It is also used by the node to enforce overall resource usage across all
containers. Not all memory is reclaimed when a container dies or restarts
and so we need an isolation sandbox that spans across all the containers.

It's not a "concept", but more of an implementation detail. Maybe we can
clarify that more explicitly until we introduce it as a concept in the
future?

On Fri, May 5, 2017 at 12:35 AM, 'David Oppenheimer' via Kubernetes user
discussion and Q  wrote:

>
>
> On Wed, May 3, 2017 at 12:10 PM, 'Ahmet Alp Balkan' via Kubernetes user
> discussion and Q  wrote:
>
>> I am afraid it still does not make sense to me.
>>
>> Why is there even a concept of "Pod-level request/limit" if it is not
>> used anywhere?
>>
>
> It is used by the scheduler. Pod is the atomic unit of scheduling.
>

>
>> As a user, this is confusing me. As far as I can tell, I can configure
>> limits on the Container and if I go beyond that my *Pod* will be killed
>> altogether. This part is clear. However I can't tell what a Pod-level
>> request/limit (just a sum of things which I can't configure directly) does
>> on my cluster today?
>>
>> On Wed, May 3, 2017 at 11:30 AM, 'David Oppenheimer' via Kubernetes user
>> discussion and Q  wrote:
>>
>>>
>>>
>>> On Wed, May 3, 2017 at 10:47 AM, 'Ahmet Alp Balkan' via Kubernetes user
>>> discussion and Q  wrote:
>>>
 Hello, I am trying to understand the Resource Limits/Requests for Pods
 and Containers
 
  document.
 In multiple places, the document implies that users can specify
 ResourceRequirements *at pod-level**. *(I don't mean
 pod.spec.containers.resources.) Most relevantly the doc says:

 A Pod resource request/limit for a particular resource type* is the
> sum *of the resource requests/limits of that type for each Container
> in the Pod.


>>> Request and limit are specified only at the per-container level. The
>>> system computes pod-level request and limit by adding up the request and
>>> limit of the containers that are inside the pod. But you can't specify it
>>> at the pod level yourself.
>>>
>>> Does that make sense?
>>>
>>>
>>>

 However I can’t find any examples or any fields on the API (kubectl
 explain pod.spec) to specify resource requirements on the pod level.

 Any ideas if this is possible at all? This particular document is
 particularly gives the strong impression that this feature exists today. I
 opened this docs issue
  to
 track this.

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Re: [kubernetes-users] Resource requests/limits on Pod-level

['David Oppenheimer' via Kubernetes user discussion and Q]

On Wed, May 3, 2017 at 12:10 PM, 'Ahmet Alp Balkan' via Kubernetes user
discussion and Q  wrote:

> I am afraid it still does not make sense to me.
>
> Why is there even a concept of "Pod-level request/limit" if it is not used
> anywhere?
>

It is used by the scheduler. Pod is the atomic unit of scheduling.


> As a user, this is confusing me. As far as I can tell, I can configure
> limits on the Container and if I go beyond that my *Pod* will be killed
> altogether. This part is clear. However I can't tell what a Pod-level
> request/limit (just a sum of things which I can't configure directly) does
> on my cluster today?
>
> On Wed, May 3, 2017 at 11:30 AM, 'David Oppenheimer' via Kubernetes user
> discussion and Q  wrote:
>
>>
>>
>> On Wed, May 3, 2017 at 10:47 AM, 'Ahmet Alp Balkan' via Kubernetes user
>> discussion and Q  wrote:
>>
>>> Hello, I am trying to understand the Resource Limits/Requests for Pods
>>> and Containers
>>> 
>>>  document.
>>> In multiple places, the document implies that users can specify
>>> ResourceRequirements *at pod-level**. *(I don't mean
>>> pod.spec.containers.resources.) Most relevantly the doc says:
>>>
>>> A Pod resource request/limit for a particular resource type* is the sum
 *of the resource requests/limits of that type for each Container in
 the Pod.
>>>
>>>
>> Request and limit are specified only at the per-container level. The
>> system computes pod-level request and limit by adding up the request and
>> limit of the containers that are inside the pod. But you can't specify it
>> at the pod level yourself.
>>
>> Does that make sense?
>>
>>
>>
>>>
>>> However I can’t find any examples or any fields on the API (kubectl
>>> explain pod.spec) to specify resource requirements on the pod level.
>>>
>>> Any ideas if this is possible at all? This particular document is
>>> particularly gives the strong impression that this feature exists today. I
>>> opened this docs issue
>>>  to
>>> track this.
>>>
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Kubernetes user discussion and Q" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to kubernetes-users+unsubscr...@googlegroups.com.
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>>> Visit this group at https://groups.google.com/group/kubernetes-users.
>>> For more options, visit https://groups.google.com/d/optout.
>>>
>>
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>>
>
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