In previous part 1 I wrote about NetApp AFF and ADP with smaller 400 GB SSD drives. This time I will concentrate on ADPv2 with larger SSD drives (3,8TB). As a reminder, with ADPv2 you can deploy 12 SSD disk setups while still having two data aggregates and two controllers serving data and thus getting better performance. So ADPv2 with 12 SSD drives is beneficial also with larger SSD drives.
Example of 12×3,8TB SSD drive setup with ADPv2. You will get roughly 29,85 TB of usable capacity or about 65,46% usable capacity out of marketing capacity.
Example of symmetric 12×3,8 TB SSD drive setup with ADPv1. Since there is only one partition available for data aggregates and no spare and parity sharing, you will get less usable capacity, roughly about 19,90 TB or 43,64% of usable capacity out of marketing capacity. Asymmetric (not shown) configuration with ADPv1 would give the same usable capacity as with ADPv2, but only one controller serving data and lower performance.
In conclusion: With ADPv2 and 12×3.8TB disks you will get ((29,85 – 19,9) / 19,9) * 100 = 50% more usable capacity than with ADPv1 and 12×3,8TB disks in symmetric configuration. Or the other way around with ADPv1 and 12×3,8TB disks in symmetric configuration you will get ((29,85 – 19,9) / 29,85 ) * 100 = 33% less usable capacity than with ADPv2 and 12×3,8TB disks. (hopefully my math is correct, calculating percentages really sucks…)
While this is already quite nice improvement, there are additional benefits to gain with ADPv2. I’ll cover these in Part 3.