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---
title: Managing Resources for Containers
content_type: concept
weight: 40
feature:
title: Automatic bin packing
description: >
Automatically places containers based on their resource requirements and other constraints, while not sacrificing availability. Mix critical and best-effort workloads in order to drive up utilization and save even more resources.
---
<!-- overview -->
When you specify a {{< glossary_tooltip term_id="pod" >}}, you can optionally specify how
much of each resource a {{< glossary_tooltip text="Container" term_id="container" >}} needs.
The most common resources to specify are CPU and memory (RAM); there are others.
When you specify the resource _request_ for Containers in a Pod, the scheduler uses this
information to decide which node to place the Pod on. When you specify a resource _limit_
for a Container, the kubelet enforces those limits so that the running container is not
allowed to use more of that resource than the limit you set. The kubelet also reserves
at least the _request_ amount of that system resource specifically for that container
to use.
<!-- body -->
## Requests and limits
If the node where a Pod is running has enough of a resource available, it's possible (and
allowed) for a container to use more resource than its `request` for that resource specifies.
However, a container is not allowed to use more than its resource `limit`.
For example, if you set a `memory` request of 256 MiB for a container, and that container is in
a Pod scheduled to a Node with 8GiB of memory and no other Pods, then the container can try to use
more RAM.
If you set a `memory` limit of 4GiB for that Container, the kubelet (and
{{< glossary_tooltip text="container runtime" term_id="container-runtime" >}}) enforce the limit.
The runtime prevents the container from using more than the configured resource limit. For example:
when a process in the container tries to consume more than the allowed amount of memory,
the system kernel terminates the process that attempted the allocation, with an out of memory
(OOM) error.
Limits can be implemented either reactively (the system intervenes once it sees a violation)
or by enforcement (the system prevents the container from ever exceeding the limit). Different
runtimes can have different ways to implement the same restrictions.
{{< note >}}
If a Container specifies its own memory limit, but does not specify a memory request, Kubernetes
automatically assigns a memory request that matches the limit. Similarly, if a Container specifies its own
CPU limit, but does not specify a CPU request, Kubernetes automatically assigns a CPU request that matches
the limit.
{{< /note >}}
## Resource types
*CPU* and *memory* are each a *resource type*. A resource type has a base unit.
CPU represents compute processing and is specified in units of [Kubernetes CPUs](#meaning-of-cpu).
Memory is specified in units of bytes.
If you're using Kubernetes v1.14 or newer, you can specify _huge page_ resources.
Huge pages are a Linux-specific feature where the node kernel allocates blocks of memory
that are much larger than the default page size.
For example, on a system where the default page size is 4KiB, you could specify a limit,
`hugepages-2Mi: 80Mi`. If the container tries allocating over 40 2MiB huge pages (a
total of 80 MiB), that allocation fails.
{{< note >}}
You cannot overcommit `hugepages-*` resources.
This is different from the `memory` and `cpu` resources.
{{< /note >}}
CPU and memory are collectively referred to as *compute resources*, or just
*resources*. Compute
resources are measurable quantities that can be requested, allocated, and
consumed. They are distinct from
[API resources](/docs/concepts/overview/kubernetes-api/). API resources, such as Pods and
[Services](/docs/concepts/services-networking/service/) are objects that can be read and modified
through the Kubernetes API server.
## Resource requests and limits of Pod and Container
Each Container of a Pod can specify one or more of the following:
* `spec.containers[].resources.limits.cpu`
* `spec.containers[].resources.limits.memory`
* `spec.containers[].resources.limits.hugepages-<size>`
* `spec.containers[].resources.requests.cpu`
* `spec.containers[].resources.requests.memory`
* `spec.containers[].resources.requests.hugepages-<size>`
Although requests and limits can only be specified on individual Containers, it
is convenient to talk about Pod resource requests and limits. 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.
## Resource units in Kubernetes
### Meaning of CPU
Limits and requests for CPU resources are measured in *cpu* units.
One cpu, in Kubernetes, is equivalent to **1 vCPU/Core** for cloud providers and **1 hyperthread** on bare-metal Intel processors.
Fractional requests are allowed. A Container with
`spec.containers[].resources.requests.cpu` of `0.5` is guaranteed half as much
CPU as one that asks for 1 CPU. The expression `0.1` is equivalent to the
expression `100m`, which can be read as "one hundred millicpu". Some people say
"one hundred millicores", and this is understood to mean the same thing. A
request with a decimal point, like `0.1`, is converted to `100m` by the API, and
precision finer than `1m` is not allowed. For this reason, the form `100m` might
be preferred.
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.
### Meaning of memory
Limits and requests for `memory` are measured in bytes. You can express memory as
a plain integer or as a fixed-point number using one of these suffixes:
E, P, T, G, M, K. You can also use the power-of-two equivalents: Ei, Pi, Ti, Gi,
Mi, Ki. For example, the following represent roughly the same value:
```shell
128974848, 129e6, 129M, 123Mi
```
Here's an example.
The following Pod has two Containers. Each Container has a request of 0.25 cpu
and 64MiB (2<sup>26</sup> bytes) of memory. Each Container has a limit of 0.5
cpu and 128MiB of memory. You can say the Pod has a request of 0.5 cpu and 128
MiB of memory, and a limit of 1 cpu and 256MiB of memory.
```yaml
apiVersion: v1
kind: Pod
metadata:
name: frontend
spec:
containers:
- name: app
image: images.my-company.example/app:v4
resources:
requests:
memory: "64Mi"
cpu: "250m"
limits:
memory: "128Mi"
cpu: "500m"
- name: log-aggregator
image: images.my-company.example/log-aggregator:v6
resources:
requests:
memory: "64Mi"
cpu: "250m"
limits:
memory: "128Mi"
cpu: "500m"
```
## How Pods with resource requests are scheduled
When you create a Pod, the Kubernetes scheduler selects a node for the Pod to
run on. Each node has a maximum capacity for each of the resource types: the
amount of CPU and memory it can provide for Pods. The scheduler ensures that,
for each resource type, the sum of the resource requests of the scheduled
Containers is less than the capacity of the node. Note that although actual memory
or CPU resource usage on nodes is very low, the scheduler still refuses to place
a Pod on a node if the capacity check fails. This protects against a resource
shortage on a node when resource usage later increases, for example, during a
daily peak in request rate.
## How Pods with resource limits are run
When the kubelet starts a Container of a Pod, it passes the CPU and memory limits
to the container runtime.
When using Docker:
- The `spec.containers[].resources.requests.cpu` is converted to its core value,
which is potentially fractional, and multiplied by 1024. The greater of this number
or 2 is used as the value of the
[`--cpu-shares`](https://docs.docker.com/engine/reference/run/#cpu-share-constraint)
flag in the `docker run` command.
- The `spec.containers[].resources.limits.cpu` is converted to its millicore value and
multiplied by 100. The resulting value is the total amount of CPU time that a container can use
every 100ms. A container cannot use more than its share of CPU time during this interval.
{{< note >}}
The default quota period is 100ms. The minimum resolution of CPU quota is 1ms.
{{</ note >}}
- The `spec.containers[].resources.limits.memory` is converted to an integer, and
used as the value of the
[`--memory`](https://docs.docker.com/engine/reference/run/#/user-memory-constraints)
flag in the `docker run` command.
If a Container exceeds its memory limit, it might be terminated. If it is
restartable, the kubelet will restart it, as with any other type of runtime
failure.
If a Container exceeds its memory request, it is likely that its Pod will
be evicted whenever the node runs out of memory.
A Container might or might not be allowed to exceed its CPU limit for extended
periods of time. However, it will not be killed for excessive CPU usage.
To determine whether a Container cannot be scheduled or is being killed due to
resource limits, see the
[Troubleshooting](#troubleshooting) section.
### Monitoring compute & memory resource usage
The resource usage of a Pod is reported as part of the Pod status.
If optional [tools for monitoring](/docs/tasks/debug-application-cluster/resource-usage-monitoring/)
are available in your cluster, then Pod resource usage can be retrieved either
from the [Metrics API](/docs/tasks/debug-application-cluster/resource-metrics-pipeline/#the-metrics-api)
directly or from your monitoring tools.
## Local ephemeral storage
<!-- feature gate LocalStorageCapacityIsolation -->
{{< feature-state for_k8s_version="v1.10" state="beta" >}}
Nodes have local ephemeral storage, backed by
locally-attached writeable devices or, sometimes, by RAM.
"Ephemeral" means that there is no long-term guarantee about durability.
Pods use ephemeral local storage for scratch space, caching, and for logs.
The kubelet can provide scratch space to Pods using local ephemeral storage to
mount [`emptyDir`](/docs/concepts/storage/volumes/#emptydir)
{{< glossary_tooltip term_id="volume" text="volumes" >}} into containers.
The kubelet also uses this kind of storage to hold
[node-level container logs](/docs/concepts/cluster-administration/logging/#logging-at-the-node-level),
container images, and the writable layers of running containers.
{{< caution >}}
If a node fails, the data in its ephemeral storage can be lost.
Your applications cannot expect any performance SLAs (disk IOPS for example)
from local ephemeral storage.
{{< /caution >}}
As a beta feature, Kubernetes lets you track, reserve and limit the amount
of ephemeral local storage a Pod can consume.
### Configurations for local ephemeral storage
Kubernetes supports two ways to configure local ephemeral storage on a node:
{{< tabs name="local_storage_configurations" >}}
{{% tab name="Single filesystem" %}}
In this configuration, you place all different kinds of ephemeral local data
(`emptyDir` volumes, writeable layers, container images, logs) into one filesystem.
The most effective way to configure the kubelet means dedicating this filesystem
to Kubernetes (kubelet) data.
The kubelet also writes
[node-level container logs](/docs/concepts/cluster-administration/logging/#logging-at-the-node-level)
and treats these similarly to ephemeral local storage.
The kubelet writes logs to files inside its configured log directory (`/var/log`
by default); and has a base directory for other locally stored data
(`/var/lib/kubelet` by default).
Typically, both `/var/lib/kubelet` and `/var/log` are on the system root filesystem,
and the kubelet is designed with that layout in mind.
Your node can have as many other filesystems, not used for Kubernetes,
as you like.
{{% /tab %}}
{{% tab name="Two filesystems" %}}
You have a filesystem on the node that you're using for ephemeral data that
comes from running Pods: logs, and `emptyDir` volumes. You can use this filesystem
for other data (for example: system logs not related to Kubernetes); it can even
be the root filesystem.
The kubelet also writes
[node-level container logs](/docs/concepts/cluster-administration/logging/#logging-at-the-node-level)
into the first filesystem, and treats these similarly to ephemeral local storage.
You also use a separate filesystem, backed by a different logical storage device.
In this configuration, the directory where you tell the kubelet to place
container image layers and writeable layers is on this second filesystem.
The first filesystem does not hold any image layers or writeable layers.
Your node can have as many other filesystems, not used for Kubernetes,
as you like.
{{% /tab %}}
{{< /tabs >}}
The kubelet can measure how much local storage it is using. It does this provided
that:
- the `LocalStorageCapacityIsolation`
[feature gate](/docs/reference/command-line-tools-reference/feature-gates/)
is enabled (the feature is on by default), and
- you have set up the node using one of the supported configurations
for local ephemeral storage.
If you have a different configuration, then the kubelet does not apply resource
limits for ephemeral local storage.
{{< note >}}
The kubelet tracks `tmpfs` emptyDir volumes as container memory use, rather
than as local ephemeral storage.
{{< /note >}}
### Setting requests and limits for local ephemeral storage
You can use _ephemeral-storage_ for managing local ephemeral storage. Each Container of a Pod can specify one or more of the following:
* `spec.containers[].resources.limits.ephemeral-storage`
* `spec.containers[].resources.requests.ephemeral-storage`
Limits and requests for `ephemeral-storage` are measured in bytes. You can express storage as
a plain integer or as a fixed-point number using one of these suffixes:
E, P, T, G, M, K. You can also use the power-of-two equivalents: Ei, Pi, Ti, Gi,
Mi, Ki. For example, the following represent roughly the same value:
```shell
128974848, 129e6, 129M, 123Mi
```
In the following example, the Pod has two Containers. Each Container has a request of 2GiB of local ephemeral storage. Each Container has a limit of 4GiB of local ephemeral storage. Therefore, the Pod has a request of 4GiB of local ephemeral storage, and a limit of 8GiB of local ephemeral storage.
```yaml
apiVersion: v1
kind: Pod
metadata:
name: frontend
spec:
containers:
- name: app
image: images.my-company.example/app:v4
resources:
requests:
ephemeral-storage: "2Gi"
limits:
ephemeral-storage: "4Gi"
- name: log-aggregator
image: images.my-company.example/log-aggregator:v6
resources:
requests:
ephemeral-storage: "2Gi"
limits:
ephemeral-storage: "4Gi"
```
### How Pods with ephemeral-storage requests are scheduled
When you create a Pod, the Kubernetes scheduler selects a node for the Pod to
run on. Each node has a maximum amount of local ephemeral storage it can provide for Pods. For more information, see [Node Allocatable](/docs/tasks/administer-cluster/reserve-compute-resources/#node-allocatable).
The scheduler ensures that the sum of the resource requests of the scheduled Containers is less than the capacity of the node.
### Ephemeral storage consumption management {#resource-emphemeralstorage-consumption}
If the kubelet is managing local ephemeral storage as a resource, then the
kubelet measures storage use in:
- `emptyDir` volumes, except _tmpfs_ `emptyDir` volumes
- directories holding node-level logs
- writeable container layers
If a Pod is using more ephemeral storage than you allow it to, the kubelet
sets an eviction signal that triggers Pod eviction.
For container-level isolation, if a Container's writable layer and log
usage exceeds its storage limit, the kubelet marks the Pod for eviction.
For pod-level isolation the kubelet works out an overall Pod storage limit by
summing the limits for the containers in that Pod. In this case, if the sum of
the local ephemeral storage usage from all containers and also the Pod's `emptyDir`
volumes exceeds the overall Pod storage limit, then the kubelet also marks the Pod
for eviction.
{{< caution >}}
If the kubelet is not measuring local ephemeral storage, then a Pod
that exceeds its local storage limit will not be evicted for breaching
local storage resource limits.
However, if the filesystem space for writeable container layers, node-level logs,
or `emptyDir` volumes falls low, the node
{{< glossary_tooltip text="taints" term_id="taint" >}} itself as short on local storage
and this taint triggers eviction for any Pods that don't specifically tolerate the taint.
See the supported [configurations](#configurations-for-local-ephemeral-storage)
for ephemeral local storage.
{{< /caution >}}
The kubelet supports different ways to measure Pod storage use:
{{< tabs name="resource-emphemeralstorage-measurement" >}}
{{% tab name="Periodic scanning" %}}
The kubelet performs regular, schedules checks that scan each
`emptyDir` volume, container log directory, and writeable container layer.
The scan measures how much space is used.
{{< note >}}
In this mode, the kubelet does not track open file descriptors
for deleted files.
If you (or a container) create a file inside an `emptyDir` volume,
something then opens that file, and you delete the file while it is
still open, then the inode for the deleted file stays until you close
that file but the kubelet does not categorize the space as in use.
{{< /note >}}
{{% /tab %}}
{{% tab name="Filesystem project quota" %}}
{{< feature-state for_k8s_version="v1.15" state="alpha" >}}
Project quotas are an operating-system level feature for managing
storage use on filesystems. With Kubernetes, you can enable project
quotas for monitoring storage use. Make sure that the filesystem
backing the `emptyDir` volumes, on the node, provides project quota support.
For example, XFS and ext4fs offer project quotas.
{{< note >}}
Project quotas let you monitor storage use; they do not enforce limits.
{{< /note >}}
Kubernetes uses project IDs starting from `1048576`. The IDs in use are
registered in `/etc/projects` and `/etc/projid`. If project IDs in
this range are used for other purposes on the system, those project
IDs must be registered in `/etc/projects` and `/etc/projid` so that
Kubernetes does not use them.
Quotas are faster and more accurate than directory scanning. When a
directory is assigned to a project, all files created under a
directory are created in that project, and the kernel merely has to
keep track of how many blocks are in use by files in that project.
If a file is created and deleted, but has an open file descriptor,
it continues to consume space. Quota tracking records that space accurately
whereas directory scans overlook the storage used by deleted files.
If you want to use project quotas, you should:
* Enable the `LocalStorageCapacityIsolationFSQuotaMonitoring=true`
[feature gate](/docs/reference/command-line-tools-reference/feature-gates/)
in the kubelet configuration.
* Ensure that the root filesystem (or optional runtime filesystem)
has project quotas enabled. All XFS filesystems support project quotas.
For ext4 filesystems, you need to enable the project quota tracking feature
while the filesystem is not mounted.
```bash
# For ext4, with /dev/block-device not mounted
sudo tune2fs -O project -Q prjquota /dev/block-device
```
* Ensure that the root filesystem (or optional runtime filesystem) is
mounted with project quotas enabled. For both XFS and ext4fs, the
mount option is named `prjquota`.
{{% /tab %}}
{{< /tabs >}}
## Extended resources
Extended resources are fully-qualified resource names outside the
`kubernetes.io` domain. They allow cluster operators to advertise and users to
consume the non-Kubernetes-built-in resources.
There are two steps required to use Extended Resources. First, the cluster
operator must advertise an Extended Resource. Second, users must request the
Extended Resource in Pods.
### Managing extended resources
#### Node-level extended resources
Node-level extended resources are tied to nodes.
##### Device plugin managed resources
See [Device
Plugin](/docs/concepts/extend-kubernetes/compute-storage-net/device-plugins/)
for how to advertise device plugin managed resources on each node.
##### Other resources
To advertise a new node-level extended resource, the cluster operator can
submit a `PATCH` HTTP request to the API server to specify the available
quantity in the `status.capacity` for a node in the cluster. After this
operation, the node's `status.capacity` will include a new resource. The
`status.allocatable` field is updated automatically with the new resource
asynchronously by the kubelet. Note that because the scheduler uses the node
`status.allocatable` value when evaluating Pod fitness, there may be a short
delay between patching the node capacity with a new resource and the first Pod
that requests the resource to be scheduled on that node.
**Example:**
Here is an example showing how to use `curl` to form an HTTP request that
advertises five "example.com/foo" resources on node `k8s-node-1` whose master
is `k8s-master`.
```shell
curl --header "Content-Type: application/json-patch+json" \
--request PATCH \
--data '[{"op": "add", "path": "/status/capacity/example.com~1foo", "value": "5"}]' \
http://k8s-master:8080/api/v1/nodes/k8s-node-1/status
```
{{< note >}}
In the preceding request, `~1` is the encoding for the character `/`
in the patch path. The operation path value in JSON-Patch is interpreted as a
JSON-Pointer. For more details, see
[IETF RFC 6901, section 3](https://tools.ietf.org/html/rfc6901#section-3).
{{< /note >}}
#### Cluster-level extended resources
Cluster-level extended resources are not tied to nodes. They are usually managed
by scheduler extenders, which handle the resource consumption and resource quota.
You can specify the extended resources that are handled by scheduler extenders
in [scheduler policy
configuration](https://github.com/kubernetes/kubernetes/blob/release-1.10/pkg/scheduler/api/v1/types.go#L31).
**Example:**
The following configuration for a scheduler policy indicates that the
cluster-level extended resource "example.com/foo" is handled by the scheduler
extender.
- The scheduler sends a Pod to the scheduler extender only if the Pod requests
"example.com/foo".
- The `ignoredByScheduler` field specifies that the scheduler does not check
the "example.com/foo" resource in its `PodFitsResources` predicate.
```json
{
"kind": "Policy",
"apiVersion": "v1",
"extenders": [
{
"urlPrefix":"<extender-endpoint>",
"bindVerb": "bind",
"managedResources": [
{
"name": "example.com/foo",
"ignoredByScheduler": true
}
]
}
]
}
```
### Consuming extended resources
Users can consume extended resources in Pod specs just like CPU and memory.
The scheduler takes care of the resource accounting so that no more than the
available amount is simultaneously allocated to Pods.
The API server restricts quantities of extended resources to whole numbers.
Examples of _valid_ quantities are `3`, `3000m` and `3Ki`. Examples of
_invalid_ quantities are `0.5` and `1500m`.
{{< note >}}
Extended resources replace Opaque Integer Resources.
Users can use any domain name prefix other than `kubernetes.io` which is reserved.
{{< /note >}}
To consume an extended resource in a Pod, include the resource name as a key
in the `spec.containers[].resources.limits` map in the container spec.
{{< note >}}
Extended resources cannot be overcommitted, so request and limit
must be equal if both are present in a container spec.
{{< /note >}}
A Pod is scheduled only if all of the resource requests are satisfied, including
CPU, memory and any extended resources. The Pod remains in the `PENDING` state
as long as the resource request cannot be satisfied.
**Example:**
The Pod below requests 2 CPUs and 1 "example.com/foo" (an extended resource).
```yaml
apiVersion: v1
kind: Pod
metadata:
name: my-pod
spec:
containers:
- name: my-container
image: myimage
resources:
requests:
cpu: 2
example.com/foo: 1
limits:
example.com/foo: 1
```
## Troubleshooting
### My Pods are pending with event message failedScheduling
If the scheduler cannot find any node where a Pod can fit, the Pod remains
unscheduled until a place can be found. An event is produced each time the
scheduler fails to find a place for the Pod, like this:
```shell
kubectl describe pod frontend | grep -A 3 Events
```
```
Events:
FirstSeen LastSeen Count From Subobject PathReason Message
36s 5s 6 {scheduler } FailedScheduling Failed for reason PodExceedsFreeCPU and possibly others
```
In the preceding example, the Pod named "frontend" fails to be scheduled due to
insufficient CPU resource on the node. Similar error messages can also suggest
failure due to insufficient memory (PodExceedsFreeMemory). In general, if a Pod
is pending with a message of this type, there are several things to try:
- Add more nodes to the cluster.
- Terminate unneeded Pods to make room for pending Pods.
- Check that the Pod is not larger than all the nodes. For example, if all the
nodes have a capacity of `cpu: 1`, then a Pod with a request of `cpu: 1.1` will
never be scheduled.
You can check node capacities and amounts allocated with the
`kubectl describe nodes` command. For example:
```shell
kubectl describe nodes e2e-test-node-pool-4lw4
```
```
Name: e2e-test-node-pool-4lw4
[ ... lines removed for clarity ...]
Capacity:
cpu: 2
memory: 7679792Ki
pods: 110
Allocatable:
cpu: 1800m
memory: 7474992Ki
pods: 110
[ ... lines removed for clarity ...]
Non-terminated Pods: (5 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits
--------- ---- ------------ ---------- --------------- -------------
kube-system fluentd-gcp-v1.38-28bv1 100m (5%) 0 (0%) 200Mi (2%) 200Mi (2%)
kube-system kube-dns-3297075139-61lj3 260m (13%) 0 (0%) 100Mi (1%) 170Mi (2%)
kube-system kube-proxy-e2e-test-... 100m (5%) 0 (0%) 0 (0%) 0 (0%)
kube-system monitoring-influxdb-grafana-v4-z1m12 200m (10%) 200m (10%) 600Mi (8%) 600Mi (8%)
kube-system node-problem-detector-v0.1-fj7m3 20m (1%) 200m (10%) 20Mi (0%) 100Mi (1%)
Allocated resources:
(Total limits may be over 100 percent, i.e., overcommitted.)
CPU Requests CPU Limits Memory Requests Memory Limits
------------ ---------- --------------- -------------
680m (34%) 400m (20%) 920Mi (11%) 1070Mi (13%)
```
In the preceding output, you can see that if a Pod requests more than 1120m
CPUs or 6.23Gi of memory, it will not fit on the node.
By looking at the `Pods` section, you can see which Pods are taking up space on
the node.
The amount of resources available to Pods is less than the node capacity, because
system daemons use a portion of the available resources. The `allocatable` field
[NodeStatus](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#nodestatus-v1-core)
gives the amount of resources that are available to Pods. For more information, see
[Node Allocatable Resources](https://git.k8s.io/community/contributors/design-proposals/node/node-allocatable.md).
The [resource quota](/docs/concepts/policy/resource-quotas/) feature can be configured
to limit the total amount of resources that can be consumed. If used in conjunction
with namespaces, it can prevent one team from hogging all the resources.
### My Container is terminated
Your Container might get terminated because it is resource-starved. To check
whether a Container is being killed because it is hitting a resource limit, call
`kubectl describe pod` on the Pod of interest:
```shell
kubectl describe pod simmemleak-hra99
```
```
Name: simmemleak-hra99
Namespace: default
Image(s): saadali/simmemleak
Node: kubernetes-node-tf0f/10.240.216.66
Labels: name=simmemleak
Status: Running
Reason:
Message:
IP: 10.244.2.75
Replication Controllers: simmemleak (1/1 replicas created)
Containers:
simmemleak:
Image: saadali/simmemleak
Limits:
cpu: 100m
memory: 50Mi
State: Running
Started: Tue, 07 Jul 2015 12:54:41 -0700
Last Termination State: Terminated
Exit Code: 1
Started: Fri, 07 Jul 2015 12:54:30 -0700
Finished: Fri, 07 Jul 2015 12:54:33 -0700
Ready: False
Restart Count: 5
Conditions:
Type Status
Ready False
Events:
FirstSeen LastSeen Count From SubobjectPath Reason Message
Tue, 07 Jul 2015 12:53:51 -0700 Tue, 07 Jul 2015 12:53:51 -0700 1 {scheduler } scheduled Successfully assigned simmemleak-hra99 to kubernetes-node-tf0f
Tue, 07 Jul 2015 12:53:51 -0700 Tue, 07 Jul 2015 12:53:51 -0700 1 {kubelet kubernetes-node-tf0f} implicitly required container POD pulled Pod container image "k8s.gcr.io/pause:0.8.0" already present on machine
Tue, 07 Jul 2015 12:53:51 -0700 Tue, 07 Jul 2015 12:53:51 -0700 1 {kubelet kubernetes-node-tf0f} implicitly required container POD created Created with docker id 6a41280f516d
Tue, 07 Jul 2015 12:53:51 -0700 Tue, 07 Jul 2015 12:53:51 -0700 1 {kubelet kubernetes-node-tf0f} implicitly required container POD started Started with docker id 6a41280f516d
Tue, 07 Jul 2015 12:53:51 -0700 Tue, 07 Jul 2015 12:53:51 -0700 1 {kubelet kubernetes-node-tf0f} spec.containers{simmemleak} created Created with docker id 87348f12526a
```
In the preceding example, the `Restart Count: 5` indicates that the `simmemleak`
Container in the Pod was terminated and restarted five times.
You can call `kubectl get pod` with the `-o go-template=...` option to fetch the status
of previously terminated Containers:
```shell
kubectl get pod -o go-template='{{range.status.containerStatuses}}{{"Container Name: "}}{{.name}}{{"\r\nLastState: "}}{{.lastState}}{{end}}' simmemleak-hra99
```
```
Container Name: simmemleak
LastState: map[terminated:map[exitCode:137 reason:OOM Killed startedAt:2015-07-07T20:58:43Z finishedAt:2015-07-07T20:58:43Z containerID:docker://0e4095bba1feccdfe7ef9fb6ebffe972b4b14285d5acdec6f0d3ae8a22fad8b2]]
```
You can see that the Container was terminated because of `reason:OOM Killed`, where `OOM` stands for Out Of Memory.
## {{% heading "whatsnext" %}}
* Get hands-on experience [assigning Memory resources to Containers and Pods](/docs/tasks/configure-pod-container/assign-memory-resource/).
* Get hands-on experience [assigning CPU resources to Containers and Pods](/docs/tasks/configure-pod-container/assign-cpu-resource/).
* For more details about the difference between requests and limits, see
[Resource QoS](https://git.k8s.io/community/contributors/design-proposals/node/resource-qos.md).
* Read the [Container](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#container-v1-core) API reference
* Read the [ResourceRequirements](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#resourcerequirements-v1-core) API reference
* Read about [project quotas](https://xfs.org/docs/xfsdocs-xml-dev/XFS_User_Guide/tmp/en-US/html/xfs-quotas.html) in XFS
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