good question! the "pgit actual" column tries to compare just the compression algorithms, similar to how the git side only counts the .pack file and not .idx/.rev/.bitmap or filesystem overhead. so both sides strip their "container" overhead to make it a fair comparison. but you're totally right that in practice the on-disk size is what you actually pay. that's why both numbers are in the table. and yes, pgit on-disk is usually larger than git aggressive. the tradeoff is that you get SQL queryability over your entire history, which git just can't do natively.