> bzip2 and xz are extremely slow to compress

This depends on the setting. At setting -19 (not even using --long or other tuning), Zstd is 10x slower to compress than bzip2, and 20x slower than xz, and it still gets a worse compression ratio for anything that vaguely looks like text!

But I agree if you look at the decompression side of things. Bzip2 and xz are just no competition for zstd or the gzip family (but then gzip and friends have worse ratios again, so we're left with zstd). Overall I agree with your point ("just use zstd") but not for the fast compression speed, if you care somewhat about ratios at least

In the LZ high compression regime where LZ can compete in terms of ratio, BWT compressors are faster to compress and slower to decompress than LZ codecs. BWT compressors are also more amenable to parallelization (check bsc and kanzi for modern implementations besides bzip3).

I'd argue it's more workload dependent, and everything is a tradeoff.

In my own testing of compressing internal generic json blobs, I found brotli a clear winner when comparing space and time.

If I want higher compatibility and fast speeds, I'd probably just reach for gzip.

zstd is good for many use cases, too, perhaps even most...but I think just telling everyone to always use it isn't necessarily the best advice.

> If I want higher compatibility and fast speeds, I'd probably just reach for gzip.

It’s slower and compresses less than zstd. gzip should only be reached for as a compatibility option, that’s the only place it wins, it’s everywhere.

EDIT: If you must use it, use the modern implementation, https://www.zlib.net/pigz/

Any claims about compressing programs are extremely data-dependent so any general claims will be false for certain test cases.

I do a lot of data compression and decompression, and I would have liked a lot to find a magic algorithm that works better than all others, to simplify my work.

After extensive tests I have found no such algorithm. Depending on the input files and depending on the compromise between compression ratio and execution times that is desired, I must use various algorithms, including zstd and xz, but also bzip2, bzip3 and even gzip.

I use quite frequently gzip (executed after lrzip preprocessing) for some very large files, where it provides better compression at a given execution time, or faster execution at a given compression ratio, than zstd with any options.

Of course for other kinds of files, zstd wins, but all the claims that zstd should be used for ALL applications are extremely wrong.

Whenever you must compress or decompress frequently, you must test all available algorithms with various parameters, to determine what works best for you. For big files, something like lrzip preprocessing must also be tested, as it can change a lot the performance of a compression algorithm.

why would one even care about compression speed on minecraft ComputerCraft machine?

size and decompression are the main limitations