# Pods Failing with "cannot allocate memory" Error

## Problem

Pods failing with "cannot allocate memory" error.

## Environment

* Platform9 Managed Kubernetes - All Versions
* CentOS Linux 7

## Answer

* Error Observed

{% tabs %}
{% tab title="Bash" %}

```bash
Mar  3 17:26:11 kubernetes-worker02 kubelet: E0303 17:26:11.092988   23949 pod_workers.go:191] Error syncing pod 00c8233c-8a81-487b-b5be-3f9befc13771 ("test(00c8233c-8a81-487b-b5be-3f9befc13771)"), skipping: failed to ensure that the pod: 00c8233c-8a81-487b-b5be-3f9befc13771 cgroups exist and are correctly applied: failed to create container for [kubepods burstable pod00c8233c-8a81-487b-b5be-3f9befc13771] : mkdir /sys/fs/cgroup/memory/kubepods/burstable/pod00c8233c-8a81-487b-b5be-3f9befc13771: cannot allocate memory
```

{% endtab %}
{% endtabs %}

* Following is the upstream issue link regarding this behavior [Docker fails to start containers with cgroup memory allocation error](https://github.com/docker/for-linux/issues/841).
* Indicates that the fix for the issue [\[LLNL 7.5 Bug\] slab leak causing a crash when using kmem control group](https://bugzilla.redhat.com/show_bug.cgi?id=1507149) should be in Kernel Version `3.10.0-1062.4.1 or later`.
* However the discussion also talks about similar issues being present/reported on Kernel version above this.

{% tabs %}
{% tab title="Bash" %}

```bash
$ uname -r
3.10.0-1160.36.2.el7.x86_64
```

{% endtab %}
{% endtabs %}

* One of the temporary workaround mentioned is to add the parameter `cgroup.memory=nokmem` to the `GRUB_CMDLINE_LINUX` line in the configuration file `/etc/default/grub`. After that,

{% tabs %}
{% tab title="Bash" %}

```bash
$ grub2-mkconfig -o /boot/grub2/grub.cfg
$ reboot
```

{% endtab %}
{% endtabs %}

Long term solution can be to upgrade the Kernel version to the latest version and see if it resolves the issue OR contact the OS vendor for further assistance.