Use copy of /var/lib/pacman/sync/community.db as a sample for experiments
Experiment 'plain':
  uncompressed size is 17757184 that is equal to original sample
  'zstd -19' compressed size is 4366994 that is 1.0084540990896713 times better than original sample
Experiment 'plain_nomd5':
  uncompressed size is 17536365 that is 1.0125920622660398 times better than original sample
  'zstd -19' compressed size is 4188019 that is 1.0515503869490563 times better than original sample
Experiment 'plain_nopgp':
  uncompressed size is 14085120 that is 1.2607051981097783 times better than original sample
  'zstd -19' compressed size is 1160912 that is 3.7934942527943547 times better than original sample
Experiment 'plain_nomd5pgp':
  uncompressed size is 13248000 that is 1.3403671497584542 times better than original sample
  'zstd -19' compressed size is 1021667 that is 4.310517027563776 times better than original sample
Experiment 'packed':
  uncompressed size is 7317679 that is 2.4266142310970458 times better than original sample
  'zstd -19' compressed size is 4145790 that is 1.062261474893808 times better than original sample
Experiment 'packed_nomd5':
  uncompressed size is 7201183 that is 2.4658703993496625 times better than original sample
  'zstd -19' compressed size is 3996814 that is 1.1018558782069918 times better than original sample
Experiment 'packed_nopgp':
  uncompressed size is 2954238 that is 6.010749303204413 times better than original sample
  'zstd -19' compressed size is 883681 that is 4.983600416892521 times better than original sample
Experiment 'packed_nomd5pgp':
  uncompressed size is 2837742 that is 6.257504734397982 times better than original sample
  'zstd -19' compressed size is 763730 that is 5.7663218676757495 times better than original sample