Gary Buhrmaster wrote:
While not exactly the same, the measured increase in size
by the Arch community for their packaging by moving from
xz to zstd was ~0.8% (and gaining a huge reduction in CPU
utilization at the decompress end).
I don't know what xz settings Arch was using, but in the case of our RPMs,
xz was being used with very conservative settings, mainly so that applying
DeltaRPMs (which recompresses the RPMs) can be done in a reasonable time
(and by the way, IIRC, the switch to zstd actually slows down that use
case!), though decompression time was also a criterion. That's why switching
to zstd was not a huge size increase. But we could have saved significant
size by using higher xz compression rates.
If Arch was using similar settings, that would explain the relatively small
size increase. But it is still a size increase.