Artem Tim wrote on Sat, Jul 11, 2020: > BTRFS WA is ~8 times higher than ext4. Average profit from compression > about 50% max. Not that hard arithmetic.
It's not that simple. The pattern used in that paper is far from a standard workload (random writes within a file with cow is just about as bad as things can get wrt. write amplification) ; so things like the sqlite db firefox uses in your home will be worse as far as that goes with btrfs even if compressed yes certainly. But if you're talking open w/ truncate (or new file), write in a single stride, close and never write again (like what happens when you upgrade packages, compile something, download something etc etc) then the difference won't be that big. As Chris said multiple times, it's hard to find the right way to measure impacts, and I don't have good solutions either, but this definitely isn't the kind of usage I make of my filesystem. I'd be tempted to believe the feedback from facebook on that one, even if adding snapshots into the mix it's not 100% clear if compression has much impact by itself either... BTW, given the size gains ws. time difference for compression I would advocate for default zstd compression instead of :1 -- I'd think another 12% compression improvement for almost no time difference isn't to be sneezed at?  https://www.spinics.net/lists/fedora-devel/msg274978.html -- Dominique _______________________________________________ devel mailing list -- firstname.lastname@example.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://email@example.com