> If you've got excess CPU capacity at night, I wonder if -Z1 or -Z2 > would speed the backup since it reduces the amount of data written > to disk. Where to find study which pg_dump compares backup speed and backup size by using various -Z options ? I'm wondering by -Z9 increases backup speed. Info-zip zip.exe -9 config option does not decrease compiression speed I expected that pg_dump uses same complression algorithm as zip.exe I'm really wondering why -Z9 decreases backup speed significantly. Andrus.
