Using lzip instead of xz for distributed tarballs

Ben Gamari ben at
Mon Jan 20 22:15:00 UTC 2020

Vanessa McHale <vamchale at> writes:

> Hello all,
> GHC is distributed as .tar.xz tarballs; I assume this is because it
> produces small tarballs. However, xz is ill-suited for archiving due to
> its lack of error recovery. Moreover, lzip produces smaller tarballs
> with GHC (I tested with ghc-8.8.2-x86_64-deb9-linux.tar) and
> decompression takes about the same amount of time.
Indeed I recall seeing the "Why xz is not suitable for archival
purposes" blog post quite a while ago and considered moving away from xz
at the time but wasn't entirely convinced that the benefits would
justify the churn, especially since xz tends to be pretty ubiquitous at
this point while lzip is a fair bit less so.

I'd be happy to hear further reasons why we should switch but I'll admit
that I still don't quite see what switching would buy us; we do have
a few backups spread across the planet so the probability of us having
to rely on the compressor for error recovery pretty small.


- Ben
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