musher0 wrote:a bit longer to create, but are perhaps a bit snappier to
unpack to RAM when you load your Puppy
LZ4 compresses less tightly (larger size), but decompresses much quicker than both gzip and xz. It's a trade off between disk IO speed and processing (decompression) and ram transfer speed. LZ4 when using multi-cores can throw out data at ram transfer speeds (extremely fast).
Reading more disk IO/decompress quickly can be quicker than less disk IO (tighter compression)/slower output (decompression).
Also bear in mind that once a program has been read in once during a session, most of that will remain memory bound (cached), such that subsequent re-runs of the same program/libs will already be in memory (cache). Especially in the case of puppy that might be say 500MB uncompressed in total, running on a PC that perhaps has 2GB or ram. Rather than loading the entire pup into ram at startup (slower bootup), just loading files as and when required will load less (gparted for instance might never even be used during a session). Slower to initially load a program (such as gparted if invoked during a session) than having it already available in memory, but no difference for subsequent re-runs of the program.
Generally not loading puppy into ram at startup, using lz4 compressed sfs's is the better overall choice
IMO. Maximising xz compression will tend to see a slower system by comparison whilst IO is more predominant, but thereafter the two tend to compare anyway (once cached).
As a example I run Debian frugally with a save partition (rather than a save file/folder) and comparing having all of that inside a sfs to having all of the filesystem in the save partition (non compressed) sees very little difference between the two. For me, having all of the data in the save partition leaving a empty main sfs means that I can also boot that as though it was a full install. There is a noticeable difference between booting full versus frugal however as with frugal all changes are being recorded in memory, not back on disk (I personally like frugal as you can just reboot without saving to undo all changes made during the session i.e. I like to keep the main system pristine/factory-fresh - I only ever tend to boot as though full when I apply updates, and then immediately reboot back to frugal again afterwards).