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Re: [idea]: Switch default compression from "xz" to "zstd" for .deb packages

On 16988 March 1977, Hideki Yamane wrote:

Today I want to propose you to change default compression format in .deb,
 {data,control}.tar."xz" to ."zst".
 I want to hear your thought about this.


# Compared to past change to xz proposal (in DebConf12)
  * More bandwidth
  * More CPUs
  * More storage bandwidth

Get us actual numbers please on how much a full Debian mirror would increase in size.
Also consider services like snapshots.

I do not think wasting space is any good idea.

## More bandwidth
According to https://www.speedtest.net/global-index, broadband bandwidth
 in Nicaragua becomes almost 10x

And elsewhere it may have gone up a different factor.
Still, there are MANY places where its still bad.

 And, xz cannot use multi core CPUs for decompression but zstd can.
It means that if we use xz, we just get 2x CPU power, but change to zst,
 we can get more than 10x CPU power than 2012.

In ideal conditions, maybe, but still, thats the first (to me) good reason. IMO not good enough to actually do it.

  - Not sure how repository size will be, need an experiment

And keep in mind the repository is mirrored a trillion times, stored in
snapshots, burned into images here and there, so any "small" increase in
size actually means a *huge* waste in the end.

If we switch formats, going to something that's at least as good as the
one we currently have should be the goal. (And I do not mean something
like "its code/algorithm is bad", really, that argument is dead before
it begins even).

Now, thats for .debs. There might be a better argument when talking
about the index files in dists/, they are read so much more often, it
*may* make more sense there.

bye, Joerg

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