When is it beneficial to use S3 Intelligent-Tiering? This is a question we often get from our clients and as a consultant, it’s my job to answer this question with: “Probably it is beneficial but it depends”. In this blog post series, we will first cover how S3 Intelligent-Tiering works, and the different variables influencing the decision followed by a second blog post where we will dive deeper into concrete examples.
It depends
– every existing consultant
The working of S3 Intelligent-Tiering
Amazon S3 Intelligent-Tiering is designed to optimize storage costs by automatically moving objects, based on their access pattern, between different storage tiers:
- Frequent Access: The starting tier for every object created in or transitioned to S3 Intelligent-Tiering. The object remains in this tier if it is being accessed or returns to this tier if an object stored in Infrequent Access, Archive Instant Access, Archive Access, or Deep Archive is accessed.
- Infrequent Access: An object is moved to this tier if it is not accessed for 30 consecutive days.
- Archive Instant Access: An object is moved to this tier if it’s not accessed for 90 consecutive days.
All the above tiers provide low latency and high throughput performance. If this is not a hard requirement for your storage you can enable S3 Intelligent-Tiering to allow storing objects in the following tiers:
- Archive Access: You can set a value between 90-730 days. If the object is not accessed during this specified value, it is moved to this tier. The standard retrieval time for an object in this tier is 3-5 hours.
- Deep Archive Access: You can set a value between 180-730 days. If the object is not accessed during this specified value, it is moved to this tier. The standard retrieval time for an object in this tier is 12 hours.
To understand how S3 Intelligent-Tiering can potentially save money by moving objects between storage tiers, it’s best to look at the relative pricing of the different storage tiers:
Storage Class Cost GB/Month ($)Discount relative to Frequent Access
Storage Class Cost GB/Month ($)Discount relative to Frequent Access
| Storage class | Cost GB/Month ($) | Discount relative to Frequent Access |
| Frequent Access | $ 0,0230 | – |
| Infrequent Access | $ 0,0125 | 46% |
| Archive Instant | $ 0,0040 | 83% |
| Archive | $ 0,0036 | 84% |
| Deep Archive | $ 0,00099 | 96% |
*The pricing is for eu-west-1, the Frequent Access tier has multiple price ranges based on consumption amounts ranging from $0,0230 to $0,021 per GB/month.
Advantages S3 Intelligent-Tiering
- Time-efficient, no need to understand access patterns and write S3 lifecycle policies to transition objects into different storage tiers
- Unlike S3 lifecycle policies that use object age, S3 Intelligent-Tiering is based on access patterns
- No costs for retrieving objects from Infrequent Access, (Instant) Archive, or Deep Archive
- S3 Intelligent-Tiering supports all S3 features
- If used in a suitable situation it can reduce storage costs significantly without the operational overhead
Disadvantages
- Extra Monitoring cost
- Monitoring cost of $0.0025 per 1000 objects
- If versioning is enabled, you pay a monitoring cost for all versions
- Lifecycle transition fee of $0.01/1000 requests for transitioning objects from S3 into S3 Intelligent-Tiering
- When you want to stop using S3 Intelligent-Tiering, the objects can only be transitioned to S3 One Zone-Infrequent Access and S3 Glacier (Instant Retrieval, Flexible Retrieval, or Deep Archive)
- Availability for S3 Intelligent-Tiering is 99,9% compared to 99,99% for S3-standard
Other considerations
- With S3 Intelligent-Tiering, objects smaller than 128KB will never transition out of the Frequent Access tier but there is no monitoring & automation cost charged for these objects.
- When using S3 lifecycle transitions to transition objects from S3 standard or Infrequent access to S3 Intelligent-Tiering, objects smaller than 128KB aren’t transitioned.
Conclusion
In the next blog post we will dive deeper into how the following variables will impact potential savings of S3 Intelligent-Tiering plus some cost-savings tips:
- Amount of objects
- Object size
- Access pattern
- Object lifetime
- Lifecycle transition fee
Sources:
- https://aws.amazon.com/s3/storage-classes/#:~:text=*%20S3%20Intelligent%2DTiering%20charges%20a,the%20monitoring%20and%20automation%20charge.
- https://aws.amazon.com/s3/storage-classes/
- https://aws.amazon.com/s3/pricing/?nc=sn&loc=4
- https://docs.aws.amazon.com/AmazonS3/latest/userguide/intelligent-tiering.html