Reply To: Incorrect answer on EBS Cold HDD

[Andrew Bowen]

<div>Just my two cents…</div>

This scenario clearly mentions 3 points:

– Throughput-oriented workload

– Lowest Cost

– Infrequent Access

AFAIK, “Throughput” is the dominant performance attribute for HDDs while it is “IOPS” for SSDs so the first keyword can refer to either st1 (throughput optimized HDD) or sc1 (Cold HDD).

The other 2 keywords are clearly in favor for Cold HDD since it’s been mentioned almost all AWS docs that it is meant for infrequently access workloads and for cases where the lowest cost is preferred:

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/hdd-vols.html

I got this question right the first time because of those keywords when I’m doing my review. The word “throughput” basically gives you the distinction in using HDD over SSD since SSD is more of “IOPS-oriented” rather than “throughput-oriented”.

I recommend to Fernando-6 to carefully consider the other related keywords and give more weight on the keywords at the end of the question which in this case, “MOST COST-EFFECTIVE”