Even compression level 1 or 2 is pretty good. I once used https://github.com/google/riegeli https://github.com/google/riegeli and a low zstd compression level

Even compression level 1 or 2 is pretty good. I once used https://github.com/google/riegeli https://github.com/google/riegeli and a low zstd compression level to store large quantities of protobuf data in an efficient manner (in terms of CPU, RAM and streaming to disk). Shame Riegeli is not well known, not well documented and does not have many tests.