LVM Pool metadata default size is too small

[brendanhoar]

Qubes OS version
R4.01 current testing

Affected component(s) or functionality
System stability - filesystems

Brief summary
It is possible for the LVM Thin Pool to approach/reach a full state on a running system without a method to resolve, leading to catastrophic results

To Reproduce
Unclear but several R4.0x users, including @tasket have run into the issue (thread: https://groups.google.com/forum/#!topic/qubes-users/qq_ElNPdx-g )

Expected behavior

1. Installation of a non-server OS should be configured with somewhat more user-oriented (e.g. non-sysadmin) default values such that system usage doesn't unexpectedly produce catastrophic results

2 Warning to be emitted when approaching potentially unrecoverable storage situations and user guided to

Actual behavior
System stops responding. On reboot VMs cannot start up or even boot up. Typical user actions to resolve may may situation worse.

Solutions you've tried
N/A

Relevant documentation you've consulted
I did not see anything addressing the issue on https://www.qubes-os.org

Related, non-duplicate issues
#5053

[andrewdavidwong]

Duplicate of #3243

[andrewdavidwong]

This appears to be a duplicate of an existing issue. If so, please comment on the appropriate existing issue instead. If you believe this is not really a duplicate, please leave a comment briefly explaining why. We'll be happy to take another look and, if appropriate, reopen this issue. Thank you.