# compression

  bzip3 -j 4 -e linux-5.18-rc6.tar linux-5.18-rc6.tar.bz3 
    user: 345.48s system: 0.59s cpu: 373% total: 1:32.75

  zstd -19 --long -T4 -f linux-5.18-rc6.tar
    user: 1270.48s system: 0.89s cpu: 376% total: 5:37.9

  > du -b linux-5.18-rc6.tar.* | sort -rn | reln
  1.000000  130907738  linux-5.18-rc6.tar.zst
  0.994715  130215881  linux-5.18-rc6.tar.bz3

With additional ‘--ultra -22’ tar.zst is smaller, but the compression time sky rockets.

  # decompression 

  bzip3 -j 4 -d linux-5.18-rc6.tar.bz3 linux-5.18-rc6.tar 
    user: 222.57s system: 0.92s cpu: 362% total: 1:01.69

  bzip3 -d linux-5.18-rc6.tar.bz3 linux-5.18-rc6.tar 
    user: 141.29s system: 0.89s cpu: 99% total: 2:22.19

  zstd -d -T4 -f linux-5.18-rc6.tar.zst 
    user: 2.26s system: 0.84s cpu: 99% total: 3.102

zstd doesn’t seem to support parallel decoding, but still 20x faster