That seems fine -- it's a tradeoff between speed and compression ratio, which has existed ever since compression went beyond RLE. Zstd competes against Snappy

That seems fine -- it's a tradeoff between speed and compression ratio, which has existed ever since compression went beyond RLE. Zstd competes against Snappy and LZ4 in the market of transmission-time compression. You use it for things like RPC sessions, where the data is being created on-the-fly, compressed for bandwidth savings, then decompressed+parsed on the other side. And in this domain, Zstd is pretty clearly the stand-out winner. When it comes to archival, the wall-clock performance is less important. Doubling the compress/decompress time for a 5% improvement in compression ratio is an attractive option, and high-compression XZ is in many cases faster than high-compression Zstd even delivering better ratios. --- EDIT for parent post adding numbers: I spot-tested running zstd with `-22 --ultra` on files in my archive of source tarballs, and wasn't able to find cases where it outperformed `xz -9`.