This DisplayString reports the total amount of free disk space in absolute terms, per 'Disk total free space,' complementing the percentage figure in diskPercent with a real capacity number. Having both matters because the same percentage means very different things on a small versus a large disk, so an admin doing capacity planning would want this absolute value, not just the percentage, to judge how many more days of logs the disk can actually hold. A diskFreeTotal reading in single-digit gigabytes on an appliance logging heavily would translate to only a few hours of runway before the disk fills.