On 2 Sep 2023 14:49 -0700, from dpchr...@holgerdanske.com (David Christensen): > So, 693 GB backup size, 98 backups, 67 TB apparent total backup storage, and > 777 GB actual total backup storage. So, a savings of about 88:1. > > What statistics are other readers seeing for similar use-cases and their > backup solutions?
8.07 TiB physically stored on one backup drive holding 174 backups; 11.4 TiB total logical (excluding effects of compression) data on the source; 7.83 TiB hot current logical data on the source (excluding things like ZFS snapshots and compression). Which by your way of calculating seems to work out to an about 246:1 savings compared to simply keeping every single copy in full and uncompressed. (Which would require almost 2 PB of storage.) But this figure is a bit exaggerated since there are parts of the backups that I prune after a while while keeping the rest of that backup, so let's be very generous and call it maybe a 100:1 savings in practice. Which is still pretty good for something that only does raw copying with whole-file deduplication. I have a wide mix of file sizes and content types; everything from tiny Maildir message files through photos in the tens of megabytes range to VM disk image files in the tens of gigabytes range, ranging from highly compressible to essentially incompressible, and ranging from files that practically never change after I initially store them to ones that change all the time. -- Michael Kjörling 🔗 https://michael.kjorling.se “Remember when, on the Internet, nobody cared that you were a dog?”
