Using lzip instead of xz for distributed tarballs

Vanessa McHale vamchale at
Tue Jan 21 16:44:15 UTC 2020

Would it be plausible to distribute both? That way users would not have to install lzip.

Vanessa McHale

> On Jan 20, 2020, at 4:15 PM, Ben Gamari <ben at> wrote:
> 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.
> Cheers,
> - Ben

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