Google Kubernetes Engine Adds Multishares for Filestore Enterprise

Published on Jan 12, 2023

Google Cloud has made Filestore Enterprise Multishares for Google Kubernetes Engine (GKE) generally available. With Filestore Enterprise Multishares, multiple persistent volumes can be packed onto a Filestore Enterprise instance in order to maximize storage efficiency and reduce costs.

Filestore Enterprise provides GKE with a fully managed, regional network-attached storage (NAS) system. The storage system is fully decoupled from the host and does not require additional infrastructure operations in order to attach or detach volumes. It is possible for hundreds to thousands of containers to read and write volumes at the same time.

When combined with the GKE Filestore Container Storage Interface (CSI) driver, Filestore Multishares is capable of allocating up to ten shares on a single Filestore Enterprise instance. In GKE, each share corresponds to a unique persistent volume (PV). PVs can be provisioned with capacities ranging from 100 GiB to 1 TiB. GKE Filestore CSI driver will bin pack volume requests onto the Filestore Enterprise instance when storage is requested via Kubernetes Persistent Volume Claim (PVC).

GKE Filestore CSI driver will automatically create more Filestore instances if the application exceeds ten PVCs. The process of creating a new Filestore share of PV can take some time. To facilitate PV creation, the StorageClass YAML file should be modified to include volumeBindingMode: Immediate.

Following the deletion of a PV, the GKE Filestore CSI driver will reclaim the storage and remove the share. If all shares have been removed, the driver will also delete the Filestore instance. There is also support for upscaling PV capacity with near-zero downtime. It is important to note that some PV deletion operations may take a considerable amount of time to complete. The creation or expansion of PVCs for the same storage class may be blocked during this period. Filestore Multishares do not support snapshots at this time. By using the Filestore API, a single share Filestore StorageClass can be used to create manual snapshots.

Several considerations should be kept in mind when using this tool, according to Saikat Roychowdhury, Senior Software Engineer at Google, and Akshay Ram, Product Manager at Google. There is a risk of a noisy neighbor consuming an excessive amount of IOPS and throughput due to the fact that the underlying Filestore is shared. PVCs should share the same trust boundary, so if stronger isolation is required, Filestore single-share instances should be used.

The GKE Filestore CSI driver must be enabled at version 1.23 or higher in order to access the Filestore Multishares feature. Please note that this feature is only available to customers of the Filestore Enterprise service tier. The Google Cloud website provides more information about Filestore Multishare.