2024-09-23 –, Hall C+D
As discussed in KVM Forum 2022, there are many good reasons why you might want to run your storage backends outside of the QEMU process that runs your VM, and the obvious answer to this is qemu-storage-daemon. But while naming a tool is an answer, it's not a full answer: QSD provides a variety of different export types – and more may be coming – that allow connecting it to the VM, and each has different performance characteristics and limitations.
In this talk, Kevin will compare the options we have, illustrated by the case of providing QSD-backed storage to Kubernetes and KubeVirt, and explore ideas for future directions and optimisations, such as adding QSD support for ublk and extending ublk on the kernel side to introduce a fast path for the common case.
Most of the considerations will apply to potential other storage daemons as well.
Kevin Wolf works at Red Hat as a KVM developer, with a focus on block devices. He is the maintainer of QEMU’s block subsystem and has contributed many patches to block device emulation and image format drivers. After graduating in Software Engineering at the University of Stuttgart, Germany in 2008 he worked on Xen’s block layer for a year before he started working on KVM for Red Hat in 2009.