If you can use the directory format, then you can use multiple jobs to really speed up compressed dump (and restore). Also, I'd suggest trying a run with lz4 compression--lz4 is particularly good at not slowing down when it encounters already-compressed data. Doesn't give really high compression ratios, but since you're already at -Z3, might be worth comparing. (Personally, I stay away from zstd, as I've seen it create malformed backups because the encoder crashes with out-of-memory.) -- Scott Ribe scott_ribe@xxxxxxxxxxxxxxxx https://www.linkedin.com/in/scottribe/ > On Oct 18, 2023, at 4:30 PM, Ron <ronljohnsonjr@xxxxxxxxx> wrote: > > In preparation for moving from 9.6 to something supported, I ran a pg_dump/pg_restore test (since the migrated databases will be on new servers, and we purge off old partitions and add new partitions, pg_upgrade and logical replication are off the table). > > (The servers are VMs on ESX hosts, and on the same subnet.) > > Our databases are chock full of bytea fields holding compressed images. pg_dump -Fd -Z6 took 25 minutes, and 5.5GB disk space. (remember, it's a test!), while pg_dump -Fd -Z0 only took 90 seconds, but consumed 15GB. > > This isn't really surprising to anyone who's ever tried to gzip a jpg file... > > Quite the speed increase if you can swallow the increased disk usage. > > pg_dump -Z3 did the best: only 8.5 minutes, while using just 5.8GB disk space. > > -- > Born in Arizona, moved to Babylonia. > >
