expanding rootfs size does not seem to work

Asking around on slack and looking at various PR/code there seems to be some ability to increase the rootfs size from 20GB. I was directed to create an issue on this repo.

Working with containerd there are several PRs that reference this (linked below) each describing containerd ns labels. We have applied those labels and they seem to have no effect.

# containerd code base
egrep -i -R 'rootfs' ./plugins | grep -E -i "label"
egrep: warning: egrep is obsolescent; using grep -E
./plugins/snapshots/lcow/lcow.go:	rootfsSizeLabel           = "containerd.io/snapshot/io.microsoft.container.storage.rootfs.size-gb"
./plugins/snapshots/lcow/lcow.go:	rootfsLocLabel            = "containerd.io/snapshot/io.microsoft.container.storage.rootfs.location"
./plugins/snapshots/lcow/lcow.go:				if sizeGBstr, ok := snapshotInfo.Labels[rootfsSizeLabel]; ok {
./plugins/snapshots/lcow/lcow.go:				scratchLocation := snapshotInfo.Labels[rootfsLocLabel]
./plugins/snapshots/windows/common.go:	if sizeGBstr, ok := snapshotInfo.Labels[rootfsSizeInGBLabel]; ok {
./plugins/snapshots/windows/common.go:		log.G(ctx).Warnf("%q label is deprecated, please use %q instead.", rootfsSizeInGBLabel, rootfsSizeInBytesLabel)
./plugins/snapshots/windows/common.go:			return 0, fmt.Errorf("failed to parse label %q=%q: %w", rootfsSizeInGBLabel, sizeGBstr, err)
./plugins/snapshots/windows/common.go:	if sizeBytesStr, ok := snapshotInfo.Labels[rootfsSizeInBytesLabel]; ok {
./plugins/snapshots/windows/common.go:			return 0, fmt.Errorf("failed to parse label %q=%q: %w", rootfsSizeInBytesLabel, sizeBytesStr, err)https://github.com/containerd/containerd/issues/6694
./plugins/snapshots/windows/windows.go:	// Deprecated: use rootfsSizeInBytesLabel
./plugins/snapshots/windows/windows.go:	rootfsSizeInGBLabel = "containerd.io/snapshot/io.microsoft.container.storage.rootfs.size-gb"
./plugins/snapshots/windows/windows.go:	// rootfsSizeInBytesLabel is a label to control a Windows containers scratch space
./plugins/snapshots/windows/windows.go:	rootfsSizeInBytesLabel = "containerd.io/snapshot/windows/rootfs.sizebytes"

For example we have tried setting both containerd.io/snapshot/windows/rootfs.sizebytes and containerd.io/snapshot/io.microsoft.container.storage.rootfs.size-gb and neither seem to impact anything.

Are we doing something wrong or is the simply not implemented end-to-end?

Thanks!

• https://github.com/containerd/containerd/pull/6918
• https://github.com/containerd/containerd/issues/7199
• https://github.com/containerd/containerd/issues/6694

Start by tracing the reported labels through containerd's plugins/snapshots/windows/common.go and plugins/snapshots/windows/windows.go, then compare the related handling in plugins/snapshots/lcow/lcow.go. Reproduce the report using both labels and document whether they reach the Windows rootfs path; done means establishing the implementation status and recording the evidence or a tested resolution.