Known Kata Container Limitations

This section describes the known limitations when using Kata containers.

SR-IOV Support

A minimal kernel and rootfs for Kata containers are shipped with StarlingX, and can be found at /usr/share/kata-containers/. To enable certain kernel features such as IOMMU, and desired network kernel modules, a custom kernel image, and rootfs has to be built. However, many tests carried out using this solution were unsuccessful. More details of this solution can be seen in: https://bugs.launchpad.net/starlingx/+bug/1867927.

CPU Manager Support

Kata containers currently occupy only the platform cores. There is no CPU manager support.

Hugepages

• Similar to the SR-IOV limitation, hugepage support must be configured in a custom Kata kernel.

• The size and number of hugepages must be written using the io.katacontainers.config.hypervisor.kernel_params annotation.

• Creating a hugetlbfs mount for hugepages in the Kata container is specific to the end user application.

Note

This solution does not work in version v3.1.3 of the Kata Containers. A pod can be started with hugepages specified, but none are actually allocated to the Kata VM.