The following example reflects a scenario where your file access patterns change over time, and includes each of EFS IA and EFS Archive's pricing dimensions. The example assumes that the two EFS Lifecycle policies to move files between EFS Standard, EFS Infrequent Access (IA), and EFS Archive are set.
Assume that your file system is located in the US East (N. Virginia) Region. At the beginning of a 31-day month, your file system stores 200 GB of files on EFS Standard, 500 GB of files on EFS IA, and 2 TB of files on EFS Archive. On the 15th day of the month, EFS Lifecycle Management, without Intelligent Tiering, moves 50% of your EFS Standard files to the EFS IA class and 10% of your EFS IA files to the EFS Archive class after 14 days of having not been accessed. On average, your client application reads 200 GB of files from your EFS IA and 100 GB of files from your EFS Archive each month.
First, we calculate the pro-rated storage usage:
Standard Storage:
200 GB of EFS Standard storage for 14 days (GB-Hours): 200 GB x 14 days x (24 hours / day) = 67,200 GB-Hours
100 GB of EFS Standard storage for 17 days (GB-Hours): 100 GB x 17 days x (24 hours / day) = 40,800 GB-Hours
Total EFS Standard storage usage (GB-Hours): 67,200 GB-Hours + 40,800 GB-Hours = 108,000 GB-Hours
IA Storage:
500 GB of EFS IA for 14 days (GB-Hours): 500 GB x 14 x (24 hours / day) = 168,000 GB-Hours
100 GB of files from EFS Standard to EFS IA for 17 days (GB-Hours) = 100 GB x 17 x (24 hours / day) = 40,800 GB-Hours
450 GB of EFS IA (after 50 GB is moved to EFS Archive) = 450 GB x 17 x (24 hours / day) = 183,600 GB-Hours
Total EFS IA usage (GB-Hours): 168,000 GB-Hours + 40,800 GB-Hours + 326,400 GB-Hours = 392,400 GB-Hours
Archive Storage:
2 TB of EFS IA for 31 days (GB-Hours): 2,000 GB x 31 x (24 hours / day) = 1,488,000 GB-Hours
50 GB of files from EFS IA to EFS Archive for 17 days (GB-Hours): 50 GB x 17 x (24 hours / day) = 20,400 GB-Hours
Total EFS Archive storage usage (GB-Hours): 1,488,000 GB-Hours + 20,400 GB-Hours = 1,508,400 GB-Hours
Next, we convert the storage usage into GB-months and calculate the storage charge:
Total EFS Standard charge: 108,000 GB-Hours x (1 month / 744 hours) x $0.30/GB-month = $43.55
Total EFS IA charge: 392,400 GB-Hours x (1 month / 744 hours) x $0.0165/GB-month = $8.70
Total EFS Archive charge: 1,508,400 GB-Hours x (1 month / 744 hours) x $0.008/GB-month = $16.22
Total EFS storage charge: $43.55 + $8.70 + $16.22 = $68.47
Next, we calculate the access charges for files in EFS IA and EFS Archive:
IA Data Tiering:
Data Tiering (files moved from EFS Standard to EFS IA): 100 GB * $0.01/GB = $1.00
IA read access charge: 200 GB * $0.01/GB = $2.00
Elastic Throughput read charge: 200 GB * $0.03/GB = $6.00
Total EFS IA tiering and access charges: $1.00 + $2.00 + $6.00 = $9.00
Archive Data Tiering:
Data Tiering (files moved from Infrequent Access to Archive): 50 GB * $0.03/GB = $1.50
Archive read access charge: 100 GB *$0.03/GB = $3.00
Elastic Throughput read charge: 100 GB * $0.03/GB = $3.00
Total EFS IA tiering and access charges: $1.50 + $3.00 + $3.00 = $7.50
Total EFS tiering and access charge: $9.00 + $7.50 = $16.50
Finally, we calculate the total EFS charge for the month:
Total monthly charges = Total storage charge + Total access charge = $68.47 + $16.50 = $84.97 (TCO - $0.0315/GB)