SUSE config: use Btrfs LZO compression for ResourceDisk

[ddiss]

Btrfs provides support for transparent compression, which can be
requested at mount time via the compress=type[:level] mount option.

As demonstrated in [1], transparent LZO compression provides a good
trade-off between compression ratio and performance, while also being
supported by legacy SUSE kernels. zstd could be considered for
modern SLE15-SP1+ / openSUSE Leap 15.1+ kernels.

Amongst other benefits, moving from ext4 to Btrfs allows for ephemeral
ResourceDisk data to be periodically and incrementally backed-up to
regular Page Blob backed disks using btrfs send/recv.

1. Btrfs compression benchmarks
   mainline kernel commit: 5c1aab1dd5445ed8bdcdbb575abc1b0d7ee5b2e7

Signed-off-by: David Disseldorp ddiss@suse.de

Description

Issue #

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[ddiss]

@rjschwei please review

[ddiss]

Thanks a lot for the review, Robert.
Code owners: Please let me know if anything's needed from me to move this along.

[narrieta]

@trstringer could you take a look? thanks!

[trstringer]

Something to consider is that the SUSE images using cloud-init as the provisioning agent seem to be using ext4. Here's the resource disk of the suse:sles-15-sp2:gen1:latest image:

$ df -T /dev/sdb1
Filesystem     Type 1K-blocks  Used Available Use% Mounted on
/dev/sdb1      ext4   7157240 32248   6741712   1% /mnt

So users going from walinuxagent -> cloud-init would introduce a change from btrfs -> ext4 now with this PR. This is not necessarily a blocking issue for me, but let me know your thoughts on that change, @rjschwei.

[rjschwei]

@trstringer yes, we switched all images to use cloud-init per customer requests and downstream work for image build setup is required. This change is for those that pull the agent directly from GitHub or build custom images that use the agent package we (SUSE) provides and do not use cloud-init.

[trstringer]

@rjschwei, ok that makes sense. So if you're fine with the different resource disk filesystems between waagent and cloud-init for SUSE images, that works for me.

[narrieta]

running automation

[narrieta]

Automation OK

[narrieta]

@ddiss - could you bring your branch up to date with develop? thanks!

[ddiss]

@ddiss - could you bring your branch up to date with develop? thanks!

Done, thanks