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Comment by linsomniac | Hacker News Reader

Part of my infrastructure uses compressed "dd" disc images. Last week I switched from using "xz" to "zstd" for them and "zstd -19" compresses almost as well as xz (1.8GB vs 1.7GB), but the threaded decompression is >10x faster (72s -> 6s).

I made this change coincidentally, the day before the xz compromise.

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I've been nothing but happy with ZSTD. Really good compression trade offs with ratios close to the best of LZMA.

ZSTD 3 is nearly as fast as LZ4 while getting a much better ratio. Consiquentially, on my linux boxes I use either ZFS or btrfs and use zstd 3 as the default for the file system.

Nearly as fast to compress, but much slower to decompress. Zstd is pretty good on decompression but LZ4 is top-tier.

Zstd is often "fast enough" in decompression for most cases, though.

It's why I use LZ4 for ZRAM. Only at RAM speeds do LZ4's speeds matter.

Additional note: I run these on servers that are not very tall but are pretty wide: 40 1.8GHz cores or so. So multi-threaded decompression really helps. I was using xz before, which doesn't support threaded decompression (according tom man page), decided to switch to zstd rather than pixz.

zstd (tries to) link to liblzma by default.

https://raw.githubusercontent.com/facebook/zstd/dev/CHANGELO...

See v1.3.0

I compile it statically without xz/lzma support

(JiaT75 contributed to zstd as well as xz)

Citation needed? https://github.com/facebook/zstd/commits/dev/?author=jiaT75

https://news.ycombinator.com/item?id=39873017

That looks like a(n unofficial) fork, not contributions to the official upstream repository.

I think there were some open PRs from that account, that got scrubbed from the account after the back door in xz was discovered. But probably nothing got merged.

Is it possible to retrieve the old branches?

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