This allows the FS to just live, uncompressed, in cache.
This is generally a bad idea, however:
- In a hypothetically super-tuned diskless image, the lack of double-cache can offset the lack of compression
- The image will have supreme read performance
- It will have the most deterministic memory behavior
By default, the squashfs file was being cached as well as the contents after extraction.
This is superfluous pressure on the cache of the OS.
However, it does help keep the image afloat through 'confignet', so
leave it on until onboot completes, then reclaim cache and disable further caching.
Rather than treat both as the same, since untethered has everything up front anyway, go ahead and extract the filesystem.
This makes the mount look more straightforward and makes it so deletion of files from
the image also frees ram.
If debugssh is not requsted, the initramfs is not needed.
Do not unshare the mount namespace, leave the kernel relevant namespace 'normal'
Remove some initramfs content to free up some memory.