On Fri, 15 Mar 2019 22:38:15 -0700 Adam Fontenot via arch-general <arch-general@xxxxxxxxxxxxx> wrote: > Hi, > > It's now been about half a year since support for zstd landed in our > packaging tools. I've been quietly using it for all my locally built > packages since then with no issues. I think it would be worthwhile to > have a discussion about whether to use zstd for officially built > packages. Here is a brief summary of negatives and positives: > > Negatives: > * Changing things takes time and might break someone's workflow. > * Zstd -19 results in slightly larger files than xz -6 (default). > > Positives: > * Change would be invisible to most users. > * Would keep Arch Linux on top of the latest in packaging tech. > * Updating would be much faster for most users. > > To expand on that last point: for reasonably fast connections, the > additional time required to decompress xz compressed packages means > that updating can actually take more time than it would for packages > that are not compressed at all! Because zstd is designed to have very > fast decompression, for a wide range of modern broadband connections > zstd -19 is the fastest algorithm to download and decompress. For > example, check out this compression test (with the Mozilla dataset): > https://quixdb.github.io/squash-benchmark/unstable/ > > Or look at my local test with the most recent Firefox package: > > Tool Compression time Size Time to DL (100 Mbps) + decompress > xz -6 5m 53s 49 MB 0m 21s > zstd -19 6m 0s 53 MB 0m 6s > > So while xz and zstd compress in about the same amount of time and > result in files of similar size, from the user's standpoint zstd > results in much faster updates. Multiply this by a few hundred > packages and you have a pretty substantial effect. > > I look forward to discussing this with you all. > > Cheers, > Adam What would be the Reason for the change to a slower less efficient method apart from it may be someones pet toy .. I say Stick with what we have it works is more efficient and quicker . Pete .
